Surface treatment agent

ABSTRACT

A surface-treating agent including at least one perfluoro(poly)ether group containing silane compound of any of the formulae (A1), (A2), (B1), (B2), (C1) and (C2): 
     
       
         
         
             
             
         
       
     
     wherein, each of symbols is as defined in the specification, and wherein a proportion of the perfluoro(poly)ether group containing silane compound having a molecular weight of 3,000 or less in the perfluoro(poly)ether group containing silane compounds of any of the above general formulae is 9 mol % or less.

TECHNICAL FIELD

The present invention relates to a surface-treating agent, specifically,the surface-treating agent comprising a perfluoro(poly)ether groupcontaining silane compound.

BACKGROUND ART

A certain fluorine-containing silane compound is known to be able toprovide excellent water-repellency, oil-repellency, antifoulingproperty, or the like when it is used in a surface treatment of a basematerial. A layer (hereinafter, referred to as a “surface-treatinglayer”) formed from a surface-treating agent comprising afluorine-containing silane compound is applied to various base materialssuch as a glass, a plastic, a fiber and a building material as aso-called functional thin film.

As such fluorine-containing silane compound, a perfluoropolyether groupcontaining silane compound which has a perfluoropolyether group in itsmain molecular chain and a hydrolyzable group bonding to a Si atom inits molecular terminal or terminal portion is known. For example, PatentDocuments 1 and 2 disclose a perfluoropolyether group containing silanecompound having a hydrolyzable group bonding to a Si atom in itsmolecular terminal or terminal portion.

PRIOR ART DOCUMENT Patent Document

Patent Document 1: International Publication No. 97/07155

Patent Document 2: JP 2008-534696 A

SUMMARY OF THE INVENTION Problem to be Solved by the Invention

The surface-treating layer is requested for high durability to provide abase material with a desired function for a long time. The layer formedfrom the surface-treating agent containing the perfluoropolyether groupcontaining silane compound has been suitably used in an optical membersuch as glasses, a touch panel or the like which is required to havelight permeability or transparency since it can exert the abovefunctions even in form of a thin film. In particular, in theseapplications, the friction durability is required to be furtherimproved.

However, a layer formed from a surface-treating agent containing aconventional perfluoropolyether group containing silane compounddescribed above is no longer necessarily enough to meet the increasingdemand to improve the friction durability.

An object of the present invention is to provide a perfluoro(poly)ethergroup containing silane compound which is able to form a layer havingwater-repellency, oil-repellency and antifouling property, waterproofproperty as well as high friction durability.

Means to Solve the Problem

As a result of intensively studying, the inventors of the presentinvention have found that, in a surface-treating agent comprising theperfluoro(poly)ether group containing silane compound, by setting theproportion of the perfluoro(poly)ether group containing silane compoundhaving a molecular weight of 3,000 or less in the perfluoro(poly)ethergroup containing silane compounds contained in the surface-treatingagent, the surface-treating layer having more excellent frictiondurability can be formed, and the inventors reach the present invention.

Therefore, according to the first aspect of the present invention, thereis provided a surface-treating agent comprising at least oneperfluoro(poly)ether group containing silane compound of any of theformulae (A1), (A2), (B1), (B2), (C1) and (C2):

wherein:

PFPE is each independently at each occurrence a group of the formula:

—(OC₄F₈)_(a)—(OC₃F₆)_(b)—(OC₂F₄)_(c)—(OCF₂)_(d)—

wherein a, b, c and d are each independently an integer of 0-200, thesum of a, b, c and d is 1 or more, and the occurrence order of therespective repeating units in parentheses with the subscript a, b, c ord is not limited in the formula;

Rf is each independently at each occurrence an alkyl group having 1-16carbon atoms which may be substituted by one or more fluorine atoms;

R¹ is each independently at each occurrence a hydrogen atom or an alkylgroup having 1-22 carbon atoms;

R² is each independently at each occurrence a hydroxyl group or ahydrolyzable group;

R¹¹ is each independently at each occurrence a hydrogen atom or ahalogen atom;

R¹² is each independently at each occurrence a hydrogen atom or a loweralkyl group;

n is, independently per a unit (—SiR¹ _(n)R² _(3-n)), an integer of 0-3;

there is at least one R² in the formulae (A1), (A2), (B1) and (B2);

X¹ is each independently a single bond or a 2-10 valent organic group;

X² is each independently at each occurrence a single bond or a divalentorganic group;

t is each independently at each occurrence an integer of 1-10;

α is each independently an integer of 1-9;

α′ is each independently an integer of 1-9;

X⁵ is each independently a single bond or a 2-10 valent organic group;

β is each independently an integer of 1-9;

β′ is each independently an integer of 1-9;

X⁷ is each independently a single bond or a 2-10 valent organic group;

γ is each independently an integer of 1-9;

γ′ is each independently an integer of 1-9;

R^(a) is each independently at each occurrence —Z—SiR⁷¹R⁷²R⁷³;

Z is each independently at each occurrence an oxygen atom or a divalentorganic group;

R⁷¹ is each independently at each occurrence R^(a′);

R^(a′) has the same definition as that of R^(a);

in R^(a), the number of Si atoms which are straightly linked via the Zgroup is up to five;

R⁷² is each independently at each occurrence a hydroxyl group or ahydrolyzable group;

R⁷³ is each independently at each occurrence a hydrogen atom or a loweralkyl group;

p is each independently at each occurrence an integer of 0-3;

q is each independently at each occurrence an integer of 0-3;

r is each independently at each occurrence an integer of 0-3;

in one R^(a), the sum of p, q and r is 3, and there is at least one R⁷²in the formula (C1) and (C2);

R^(b) is each independently at each occurrence a hydroxyl group or ahydrolyzable group;

R^(c) is each independently at each occurrence a hydrogen atom or alower alkyl group;

k is each independently at each occurrence an integer of 1-3;

l is each independently at each occurrence an integer of 0-2;

m is each independently at each occurrence an integer of 0-2; and

the sum of k, l and m is 3 in each unit in parentheses with thesubscript γ,

wherein a proportion of the perfluoro(poly)ether group containing silanecompound having a molecular weight of 3,000 or less in theperfluoro(poly)ether group containing silane compounds of any of theabove general formulae is 9 mol % or less.

According to the second aspect of the present invention, there isprovided a pellet comprising the surface-treating agent described above.

According to the third aspect of the present invention, there isprovided an article comprising a base material and a layer which isformed on a surface of the base material from the surface-treating agentcomprising the perfluoro(poly)ether group containing silane compounddescribed above.

Effect of the Invention

According to the present invention, there is provided a novelsurface-treating agent comprising a perfluoropolyether group containingsilane compound. By using the surface-treating agent, thesurface-treating layer having water-repellency, oil-repellency andantifouling property as well as excellent friction durability can beformed.

EMBODIMENTS TO CARRY OUT THE INVENTION

Hereinafter, the compound of the present invention will be described.

A “hydrocarbon group” as used herein represents a group containing acarbon atom and a hydrogen atom which is obtained by removing a hydrogenatom from a hydrocarbon. Examples of the hydrocarbon group include, butare not particularly limited to, a hydrocarbon group having 1-20 carbonatoms which may be substituted with one or more substituents, forexample, an aliphatic hydrocarbon group, an aromatic hydrocarbon group,and the like. The “aliphatic hydrocarbon group” may be straight,branched or cyclic, and may be saturated or unsaturated. The hydrocarbongroup may contain one or more ring structures. It is noted that thehydrocarbon group may have one or more N, O, S, Si, amide, sulfonyl,siloxane, carbonyl, carbonyloxy, or the like at its end or in itsmolecular chain.

As used herein, examples of the substituent of the “hydrocarbon group”include, but are not particularly limited to, for example a halogenatom; and a C₁₋₆ alkyl group, a C₂₋₆ alkenyl group, a C₂₋₆ alkynylgroup, a C₃₋₁₀ cycloalkyl group, a C₃₋₁₀ unsaturated cycloalkyl group, a5-10 membered heterocyclyl group, a 5-10 membered unsaturatedheterocyclyl group, a C₆₋₁₀ aryl group, a 5-10 membered heteroarylgroup, and the like, which may be substituted by one or more halogenatoms.

A “2-10 valent organic group” as used herein represents a 2-10 valentgroup containing a carbon atom. Examples of the 2-10 valent organicgroup include, but are not particularly limited to, a 2-10 valent groupobtained by removing 1-9 hydrogen atoms from a hydrocarbon group. Forexample, examples of the divalent organic group include, but are notparticularly limited to, a divalent group obtained by removing onehydrogen atom from a hydrocarbon group from a hydrocarbon group.

The present invention provides a surface-treating agent (hereinafter,referred to also as “the surface-treating agent of the presentinvention”) comprising at least one perfluoro(poly)ether groupcontaining silane compound of any of the following formulae (A1), (A2),(B1), (B2), (C1) and (C2) wherein a proportion of theperfluoro(poly)ether group containing silane compound having a molecularweight of 3,000 or less in the perfluoro(poly)ether group containingsilane compounds of the general formulae is 9 mol % or less.

Hereinafter, the compound of the formulae (A1), (A2), (B), (B2), (C1)and (C2) described above are described.

Formulae (A1) and (A2):

In the formula described above, PFPE is—(OC₄F₈)_(a)—(OC₃F₆)_(b)—(OC₂F₄)_(c)—(OCF₂)_(d)—, and corresponds to aperfluoro(poly)ether group. Herein, a, b, c and d are each independently0 or an integer of 1 or more. The sum of a, b, c and d is 1 or more.Preferably, a, b, c and d are each independently an integer of 0 or moreand 200 or less, for example an integer of 1 or more and 200 or less,more preferably each independently an integer of 0 or more and 100 orless. The sum of a, b, c and d is preferably 5 or more, more preferably10 or more, for example 10 or more and 100 or less. The occurrence orderof the respective repeating units in parentheses with the subscript a,b, c or d is not limited in the formula. Among these repeating units,the —(OC₄F₈)— group may be any of —(OCF₂CF₂CF₂CF₂)—, —(OCF(CF₃) CF₂CF₂),—(OCF₂CF(CF₃) CF₂), —(OCF₂CF₂CF(CF₃))—, —(OC(CF₃)₂CF₂)—,—(OCF₂C(CF₃)₂)—, —(OCF(CF₃) CF(CF₃))—, —(OCF(C₂F₅) CF₂)— and—(OCF₂CF(C₂F₅))—, preferably —(OCF₂CF₂CF₂CF₂)—. The —(OC₃F₆)— group maybe any of —(OCF₂CF₂CF₂)—, —(OCF(CF₃) CF₂)— and —(OCF₂CF(CF₃))—,preferably —(OCF₂CF₂CF₂)—. The —(OC₂F₄)— group may be any of —(OCF₂CF₂)—and —(OCF(CF₃))—, preferably —(OCF₂CF₂)—.

In one embodiment, PFPE is —(OC₃F₆)_(b)— wherein b is an integer of 1 ormore and 200 or less, preferably 5 or more and 200 or less, morepreferably 10 or more and 200 or less, preferably —(OCF₂CF₂CF₂)_(b)—wherein b is an integer of 1 or more and 200 or less, preferably 5 ormore and 200 or less, more preferably 10 or more and 200 or less, or—(OCF(CF₃)CF₂)_(b)— wherein b is an integer of 1 or more and 200 orless, preferably 5 or more and 200 or less, more preferably 10 or moreand 200 or less, more preferably —(OCF₂CF₂CF₂)_(b)— wherein b is aninteger of 1 or more and 200 or less, preferably 5 or more and 200 orless, more preferably 10 or more and 200 or less.

In another embodiment, PFPE is—(OC₄F₈)_(a)—(OC₃F₆)_(a)—(OC₂F₄)_(c)—(OCF₂)_(d)— wherein a and b areeach independently an integer of 0 or more and 30 or less, c and d areeach independently an integer of 1 or more and 200 or less, preferably 5or more and 200 or less, more preferably 10 or more and 200 or less, andthe occurrence order of the respective repeating units in parentheseswith the subscript a, b, c or d is not limited in the formula;preferably—(OCF₂CF₂CF₂CF₂)_(a)—(OCF₂CF₂CF₂)_(b)—(OCF₂CF₂)_(c)—(OCF₂)_(d)—. In oneembodiment, PFPE may be —(OC₂F₄)_(c)—(OCF₂)_(d)— wherein c and d areeach independently an integer of 1 or more and 200 or less, preferably 5or more and 200 or less, more preferably 10 or more and 200 or less, andthe occurrence order of the respective repeating units in parentheseswith the subscript c or d is not limited in the formula.

In further another embodiment, PFPE is a group of —(OC₂F₄—R⁸)_(f)—. Inthe formula, R⁸ is a group selected from OC₂F₄, OC₃F₆ and OC₄F₈, or acombination of 2 or 3 groups independently selected from these groups.Examples of the combination of 2 or 3 groups independently selected fromOC₂F₄, OC₃F₆ and OC₄F₈ include, but not limited to, for example,—OC₂F₄OC₃F₆—, —OC₂F₄OC₄F₈—, —OC₃F₆OC₂F₄—, OC₃F₆OC₃F₆—, —OC₃F₆OC₄F₈—,—OC₄F₈OC₄F₈—, —OC₄F₈OC₃F₈—, —OC₄F₆OC₂F₄—, —OC₂F₄OC₂F₄OC₃F₆—,—OC₂F₄OC₂F₄OC₄F₈—, —OC₂F₄OC₃F₆OC₂F₄—, —OC₂F₄OC₃F₆OC₃F₆—,—OC₂F₄OC₄F₈OC₂F₄—, OC₃F₆OC₂F₄OC₂F₄—, —OC₃F₆OC₂F₄OC₃F₆—,—OC₃F₆OC₃F₆OC₂F₄—, —OC₄F₈OC₂F₄₀C₂F₄—, and the like. f is an integer of2-100, preferably an integer of 2-50. In the above-mentioned formula,OC₂F₄, OC₃F₆ and OC₄F₈ may be straight or branched, preferably straight.In this embodiment, PFPE is preferably —(OC₂F₄—OC₃F₆)_(f)— or—(OC₂F₄—OC₄F₈)—.

In the formula, Rf is an alkyl group having 1-16 carbon atoms which maybe substituted by one or more fluorine atoms.

The “alkyl group having 1-16 carbon atoms” in the alkyl having 1-16carbon atoms which may be substituted by one or more fluorine atoms maybe straight or branched, and preferably is a straight or branched alkylgroup having 1-6 carbon atoms, in particular 1-3 carbon atoms, morepreferably a straight alkyl group having 1-3 carbon atoms.

Rf is preferably an alkyl having 1-16 carbon atoms substituted by one ormore fluorine atoms, more preferably a CF₂H—C₁₋₁₅ fluoroalkylene group,more preferably a perfluoroalkyl group having 1-16 carbon atoms.

The perfluoroalkyl group having 1-16 carbon atoms may be straight orbranched, and preferably is a straight or branched perfluoroalkyl grouphaving 1-6 carbon atoms, in particular 1-3 carbon atoms, more preferablya straight perfluoroalkyl group having 1-3 carbon atoms, specifically—CF₃, —CF₂CF₃ or —CF₂CF₂CF₃.

In the formula, R¹ is each independently at each occurrence a hydrogenatom or an alkyl group having 1-22 carbon atoms preferably an alkylgroup having 1-4 carbon atoms.

In the formula, R² is each independently at each occurrence a hydroxylgroup or a hydrolyzable group.

The “hydrolyzable group” as used herein represents a group which is ableto be removed from a backbone of a compound by a hydrolysis reaction.Examples of the hydrolyzable group include —OR, —OCOR, —O—N═CR₂, —NR₂,—NHR, halogen (wherein R is a substituted or non-substituted alkyl grouphaving 1-4 carbon atoms), preferably —OR (i.e. an alkoxy group).Examples of R include a non-substituted alkyl group such as a methylgroup, an ethyl group, a propyl group, an isopropyl group, an n-butylgroup, an isobutyl group; and a substituted alkyl group such as achloromethyl group. Among them, an alkyl group, in particular anon-substituted alkyl group is preferable, a methyl group or an ethylgroup is more preferable. The hydroxyl group may be, but is notparticularly limited to, a group generated by hydrolysis of ahydrolyzable group.

In the formula, R¹¹ is each independently at each occurrence a hydrogenatom or a halogen atom. The halogen atom is preferably an iodine atom, achlorine atom, a fluorine atom, more preferably a fluorine atom.

In the formula, R¹² is each independently at each occurrence a hydrogenatom or a lower alkyl group. The lower alkyl group is preferably analkyl group having 1-20 carbon atoms, more preferably an alkyl grouphaving 1-6 carbon atoms, for example a methyl group, an ethyl group, anpropyl group, or the like.

In the formula, n is, independently per a unit (—SiR¹ _(n)R² _(3-n)), aninteger of 0-3, preferably 0-2, more preferably 0. All of n are notsimultaneously 0 in the formula. In other words, at least one R² ispresent in the formula.

In the formula, X¹ is each independently a single bond or a 2-10 valentorganic group. X¹ is recognized to be a linker which connects between aperfluoropolyether moiety (i.e., an Rf—PFPE moiety or —PFPE- moiety)providing mainly water-repellency, surface slip property and the likeand a silane moiety (i.e., a group in parentheses with the subscript a)providing an ability to bind to a base material in the compound of theformula (A1) and (A2). Therefore, X¹ may be any organic group as long asthe compound of the formula (A1) and (A2) can stably exist.

In the formula, α is an integer of 1-9, and α′ is an integer of 1-9. αand α′ may be varied depending on the valence number of the X¹ group. Inthe formula (A1), the sum of α and α′ is the valence number of X¹. Forexample, when X¹ is a 10 valent organic group, the sum of α and α′ is10, for example, α is 9 and α′ is 1, α is 5 and α′ is 5, or α is 1 andα′ is 9. When X¹ is a divalent organic group, a and α′ are 1. In theformula (A2), α is a value obtained by subtracting 1 from the valencenumber of X¹.

X¹ is preferably a 2-7 valent, more preferably 2-4 valent, morepreferably a divalent organic group.

In one embodiment, X¹ is a 2-4 valent organic group, a is 1-3, and α′ is1.

In another embodiment, X¹ is a divalent organic group, α is 1, and α′is 1. In this case, the formulae (A1) and (A2) are represented by thefollowing formulae (A1′) and (A2′).

Examples of X¹ include, but are not particularly limited to, for examplea divalent group of the following formula:

—(R³¹)_(p′)—(X^(a))_(q′)—

wherein:

R³¹ is a single bond, —(CH₂)_(s′)- or an o-, m- or p-phenylene group,preferably —(CH₂)_(s)—,

s′ is an integer of 1-20, preferably an integer of 1-6, more preferablyan integer of 1-3, further more preferably 1 or 2,

X^(a) is —(X^(b))_(l′)—,

X^(b) is each independently at each occurrence a group selected from thegroup consisting of —O—, —S—, an o-, m- or p-phenylene group, —C(O)O—,—Si(R³³)₂—, —(Si(R³³)₂O)_(m′)—Si(R³³)₂—, —CONR³⁴—, —O—CONR³⁴—, —NR³⁴—and —(CH₂)_(n′)—,

R³³ is each independently at each occurrence a phenyl group, a C₁₋₆alkyl group or a C₁₋₆ alkoxy group, preferably a phenyl group or a C₁₋₆alkyl group, more preferably a methyl group,

R³⁴ is each independently at each occurrence a hydrogen atom, a phenylgroup or a C₁₋₆ alkyl group (preferably a methyl group),

m′ is each independently at each occurrence an integer of 1-100,preferably an integer of 1-20,

n′ is each independently at each occurrence an integer of 1-20,preferably an integer of 1-6, more preferably an integer of 1-3,

l′ is an integer of 1-10, preferably an integer of 1-5, more preferablyan integer of 1-3,

p′ is 0 or 1,

q′ is 0 or 1, and

at least one of p′ and q′ is 1, and the occurrence order of therespective repeating units in parentheses with the subscript p′ or q′ isnot limited in the formula. Here, R³¹ and X^(a) (typically, a hydrogenatom in R³¹ and X^(a)) may be substituted with one or more substituentsselected from a fluorine atom, a C₁₋₃ alkyl group and a C₁₋₃ fluoroalkylgroup.

Preferably, X¹ is —(R³¹)_(p′)—(X^(a))_(q′)—R³²—. R³² is a single bond,—(CH₂)_(t′)- or an o-, m- or p-phenylene group, preferably —(CH₂)_(t′)—.t′ is an integer of 1-20, preferably an integer of 2-6, more preferablyan integer of 2-3. Here, R³² (typically, a hydrogen atom in R³²) may besubstituted with one or more substituents from a fluorine atom, a C₁₋₃alkyl group and a C₁₋₃ fluoroalkyl group.

Preferably, X¹ may be

a C₁₋₂₀ alkylene group,—R³¹—X^(c)—R³²—, or—X^(d)—R³²wherein R³¹ and R³² are as defined above.

More preferably, X¹ may be

a C₁₋₂₀ alkylene group,—(CH₂)_(s′)—X^(c),(CH₂)_(s′)—X^(c)—(CH₂)_(t′)—

—X^(d)—, or

—X^(d)—(CH₂)_(t′)—,wherein s′ and t′ are as defined above.

In the formula, X^(c) is

—O—, —S—, —C(O)O—, —CONR³⁴—, —O—CONR³⁴—,

—Si(R³³)₂—,—(Si(R³³)₂O)_(m′)—Si(R³³)₂—,—O—(CH₂)_(u)—(Si(R³³)₂O)_(m′)—Si(R³³)₂—,—O—(CH₂)_(u′)—Si(R³³)₂—O—Si(R³³)₂—CH₂CH₂—Si(R³³)₂—O—Si(R³³)₂—,—O—(CH₂)_(u′)—Si(OCH₃)₂OSi(OCH₃)₂—,—CONR³⁴—(CH₂)_(u′)—(Si(R³³)₂O)_(m′)—Si(R³³)₂—,—CONR³⁴—(CH₂)_(u)—N(R³⁴⁾—, or—CONR³⁴-(o-, m- or p-phenylene)-Si(R³³)₂—wherein R³³, R³⁴ and m′ are as defined above, and

u′ is an integer of 1-20, preferably an integer of 2-6, more preferablyan integer of 2-3. X^(c) is preferably —O—.

In the formula, X^(d) is

—S—, —C(O)O—, —CONR³⁴—,

—CONR³⁴—(CH₂)_(u′)—(Si(R³³)₂O)_(m′)—Si(R³³)₂—,—CONR³⁴—(CH₂)_(u′)—N(R³⁴)—, or—CONR³⁴-(o-, m- or p-phenylene)-Si(R³³)₂—wherein each of symbols is as defined above.

more preferably, X¹ is

a C₁₋₂₀ alkylene group,—(CH₂)_(s′)—X^(c)—(CH₂)_(t′)— or—X^(d)—(CH₂)_(t′)—,wherein each of symbols is as defined above.

Further more preferably, X¹ is

a C₁₋₂₀ alkylene group,—(CH₂)_(s′)—O—(CH₂)_(t′)—,—(CH₂)_(s′)—(Si(R³³)₂O)_(m′)—Si(R³³)₂—(CH₂)_(t′)—,—(CH₂)_(s′)—O—(CH₂)_(u′)—(Si(R³³)₂—Si(R³³)₂O)_(m′)—(R³³)₂—(CH₂)_(t′)- or—(CH₂)_(s′)—O—(CH₂)_(t′)—Si(R³³)₂—(CH₂)_(u′)—Si(R³³)₂—(C_(v)H_(2v))—wherein R³³, m′, s′, t′ and u′ are as defined above, and v is an integerof 1-20, preferably an integer of 2-6, more preferably an integer of2-3.

In the formula, —(C_(v)H_(2v))— may be straight or branched, forexample, may be, for example, —CH₂CH₂—, —CH₂CH₂CH₂—, —CH(CH₃)—,—CH(CH₃)CH₂—.

X¹ may be substituted with one or more substituents selected from afluorine atom, a C₁₋₃ alkyl group and a C₁₋₃ fluoroalkyl group(preferably, a C₁₋₃ perfluoroalkyl group)

In another embodiment, examples of X¹ include, for example, thefollowing groups:

wherein R⁴¹ is each independently a hydrogen atom, a phenyl group, analkyl group having 1-6 carbon atoms, or a C₁₋₆ alkoxy group, preferablya methyl group;

D is a group selected from:

—CH₂O(CH₂)₂—,—CH₂O(CH₂)₃—,—CF₂O(CH₂)₃—,—(CH₂)₂—,—(CH₂)₃—,—(CH₂)₄—,—CONH—(CH₂)₃—,—CON(CH₃)—(CH₂)₃—,—CON(Ph)-(CH₂)₃— (wherein Ph is a phenyl group), and

wherein R⁴² is each independently a hydrogen atom, a C₁₋₆ alkyl group,or a C₁₋₆ alkoxy group, preferably a methyl group or a methoxy group,more preferably a methyl group,

E is —(CH₂)_(n)— wherein n is an integer of 2-6, and

D binds to PFPE of the main backbone, and E binds to a group opposite toPFPE.

Specific examples of X¹ include, for example:

—CH₂O(CH₂)—,—CHO(CH₂)₃—,—CHO(CH₂)₆—,—CH₂O(CH₂)₃Si(CH₃)₂OSi(CH₃)₂(CH₂)₂—,—CH₂O(CH₂)₃Si(CH₃)OSi(CH₃)₂OSi(CH₃)₂(CH₂)₂—,—CH₂O(CH₂)₃Si(CH₂)₂O(Si(CH₃)₂O)Si(CH₃)₂(CH₂)₂—,—CH₂O(CH₂)₃Si(CH₃)₂O(Si(CH₃)₂O)₃Si(CH₃)₂(CH₂)₂—,—CH₂O(CH₂)₃Si(CH₃)₂O(Si(CH₃)₂O)₁₀Si(CH₂)₂(CH₂)₂—,—CH₂O(CH₂)₃Si(CH₃)₂O(Si(CH₃)₂O)₂₀Si(CH₃)₂(CH₂)₂—,—CH₂OCF₂CHFOCF₂—,—CH₂OCF₂CHFOCF₂CF₂—,—CH₂OCF₂CHFOCF₂CF₂CF₂—,—CH₂OCH₂CF₂CF₂OCF₂—,—CH₂OCH₂CF₂CF₂OCF₂CF₂—,—CH₂OCH₂CF₂CF₂OCF₂CF₂CF₂—,—CH₂OCH₂CF₂CF₂OCF(CF₃)CF₂OCF₂—,—CH₂OCH₂CF₂CF₂OCF(CF₃) CF₂OCF₂CF₂—,—CH₂OCH₂CF₂CF₂OCF(CF₃)CF₂OCF₂CF₂CF₂—,—CH₂OCH₂CHFCF₂OCF₂—,—CH₂OCH₂CHFCF₂OCF₂CF₂—,—CH₂OCH₂CHFCF₂OCF₂CF₂CF₂—,—CH₂OCH₂CHFCF₂OCF(CF₃) CF₂OCF₂—,—CH₂OCH₂CHFCF₂OCF(CF₃) CF₂OCF₂CF₂—,—CH₂OCH₂CH₂FCF₂OCF(CF₃) CF₂OCF₂CF₂CF₂—,-CH₂OCH₂(CH₂)₇CH₂Si(OCH₃)₂OSi(OCH₃)₂(CH₂)₂Si(OCH₃)₂OSi(OCH₃)₂(CH₂)₂—,—CHOCH₂CH₂CH₂Si(OCH₃)₂OSi(OCH₃)₂(CH₂)₃—,—CH₂OCH₂CH₂CH₂Si(OCH₂CH₃)₂OSi(OCH₂CH₃)₂(CH₂)₃—,—CH₂OCH₂CH₂CH₂Si(OCH₃)₂OSi(OCH₃)₂(CH)₂—,—CH₂OCH₂CHCH₂Si(OCH₂CH₃)OSi(OCH₂CH₃)₂(CH₂)₂—,—(CH₂)₂—,

—(CH₂)—,

—(CH₂)₄—,—(CH₂)₆—,—(CH₂)₂—Si(CH₃)₂—(CH₂)₂——CONH—(CH₂)₃—,—CON(CH)—(CH₂)₃—,—CON(Ph)-(CH₂)₃— (wherein Ph is phenyl),—CONH—(CH₂)₆—,—CON(CH₃)—(CH₂)₆—,—CON(Ph)-(CH₂)₆— (wherein Ph is phenyl),—CONH—(CH₂)₂NH(CH₂)₃—,—CONH—(CH₂)₆NH(CH₂)₃—,—CH₂O—CONH—(CH₂)₃—,—CH₂O—CONH—(CH₂)₆—,—S—(CH₂)₃—,—(CH₂)₂S(CH₂)₃,—CONH—(CH₂)₃Si(CH₃)₂OSi(CH₃)₂(CH₂)₂—,—CONH—(CH₂)₃Si CH₃)₂OSi(CH₃)₂OSi(CH₃)₂(CH₂)₂—,—CONH—(CH₂)₃Si(CH₃)₂O(Si(CH₃)₂O)₂Si(CH₃)₂(CH₂)₂—,—CONH—(CH₂)₃Si(CH₃)₂O(Si(CH₃)₂O)₃Si(CH₃)₂(CH₂)₂—,—CONH—(CH₂)₃Si(CH₃)₂O(Si(CH₂)₂O)₁₀Si(CH₃)₂(CH₂)₂—,—CONH—(CH₂)₃Si(CH₃)₂O(Si(CH₃)₂O)₂₀Si(CH₃)₂(CH₂)₂—,—C(O)O—(CH₂)₃,—C(O)O—(CH₂)₆—,—CH₂—O—(CH₂)₃—Si(CH₃)₂—(CH₂)₂—Si(CH₃)₂—(CH₂)₂—,—CH₂—O—(CH₂)₃—Si(CH₃)—(CH₂)₂—Si(CH₃)₂—CH(CH₃)—,—CH₂—O—(CH₂)₃—Si(CH₃)₂—(CH₂)₂—Si(CH)₂—Si(CH₂)₃—(CH₂)₃—,—CH₂—O—(CH₂)₃—Si(CH₃)₂—(CH₂)₂—Si(CH₃)₂—CH(CH₃)—CH₂—,

In another preferable embodiment, X¹ is a group of the formula:—(R¹⁶)_(x)—(CFR¹⁷)_(y)—(CH₂)_(z)—. In the formula, x, y and z are eachindependently an integer of 0-10, the sum of x, y and z is 1 or more,and the occurrence order of the respective repeating units inparentheses is not limited in the formula.

In the formula, R¹⁶ is each independently at each occurrence an oxygenatom, phenylene, carbazolylene, —NR²⁶— (wherein R²⁶ is a hydrogen atomor an organic group) or a divalent organic group. Preferably, R¹⁶ is anoxygen atom or a divalent polar group.

Examples of the “divalent polar group” include, but are not particularlylimited to, —C(O)—, —C(═NR²⁷)—, and —C(O)NR²⁷— wherein R²⁷ is a hydrogenatom or a lower alkyl group. The “lower alkyl group” is, for example, analkyl group having 1-6 carbon atoms, for example, methyl, ethyl,n-propyl, which may be substituted by one or more fluorine atoms.

In the formula, R¹⁷ is each independently at each occurrence a hydrogenatom, a fluorine atom or a lower fluoroalkyl group, preferably afluorine atom. The “lower fluoroalkyl group” is, for example, preferablya fluoroalkyl group having 1-6 carbon atoms, preferably 1-3 carbonatoms, preferably a perfluoroalkyl group having 1-3 carbon atoms, morepreferably a trifluoromethyl group, and a pentafluoroethyl group,further preferably a trifluoromethyl group.

In this embodiment, X¹ is preferably is a group of the formula:—(O)_(x)—(CF₂)_(y)—(CH₂)_(z)— wherein x, y and z are as defined above,and the occurrence order of the respective repeating units inparentheses is not limited in the formula.

Examples of the group of the formula: —(O)_(x)—(CF₂)_(y)—(CH₂)_(z)—include, for example, —(O)_(x′)—(CH₂)_(z)″-O—[(CH₂)_(z′″)—O-]_(z″″), and—(O)_(x′)—(CF₂)_(y″)—(CH₂)_(z)″-O(CH₂)_(z)″-O—[(CH₂)_(z′″)—O—]_(z″″)wherein x′ is 0 or 1, y″, z″ and z″″ are each independently an integerof 1-10, and z″″ is 0 or 1. It is noted that these groups are attachedto PFPE at its left side terminal.

In another preferable embodiment, X¹ is —O—CFR¹³—(CF₂)_(e)—.

R¹³ is each independently a fluorine atom or a lower fluoroalkyl group.The lower fluoroalkyl group is, for example, a fluoroalkyl group having1-3 carbon atoms, preferably a perfluoroalkyl group having 1-3 carbonatoms, more preferably a trifluoromethyl group, and a pentafluoroethylgroup, further preferably a trifluoromethyl group.

e is each independently 0 or 1.

In one embodiment, R¹³ is a fluorine atom, and e is 1.

In another embodiment, examples of X¹ include the following groups:

wherein R⁴¹ is each independently a hydrogen atom, a phenyl group, analkyl group having 1-6 carbon atoms, or a C₁₋₆ alkoxy group, preferablya methyl group;

in each X¹, some of T are a following group which binds to PFPE of themain backbone:

—CH₂O(CH₂)₂—,—CH₂O(CH₂)₃—,—CF₂O(CH₂)₃—,—(CH₂)₂—,—(CH₂)₃—,—(CH₂)₄—,—CONH—(CH₂)₃—,—CON(CH₃)—(CH₂)₃—,—CON(Ph)-(CH₂)₃— (wherein Ph is phenyl), or

wherein R⁴² is each independently a hydrogen atom, a C₁₋₆ alkyl group,or a C₁₋₆ alkoxy group, preferably a methyl group or a methoxy group,more preferably a methyl group,

some of the other T are —(CH₂)_(n)″— (wherein n″ is an integer of 2-6)attached to the group opposite to PFPE which is a molecular backbone(i.e., a carbon atom in the formulae (A1) and (A2), and a Si atom in theformulae (B1), (B2), (C1) and (C2)), and

the others T are each independently a methyl group, a phenyl group, or aC₁₋₆ alkoxy or a radical scavenger group or an ultraviolet ray absorbinggroup, if present.

The radical scavenger group is not limited as long as it can trap aradical generated by light irradiation, and includes, for example, aresidue of benzophenones, benzotriazoles, benzoic esters, phenylsalicylates, crotonic acids, malonic esters, organoacrylates, hinderedamines, hindered phenols, or triazines.

The ultraviolet ray absorbing group is not limited as long as it canabsorb an ultraviolet ray, and includes, for example, benzotriazoles,hydroxybenzophenones, esters of benzoic acid or salicylic acid,acrylates, alkoxycinnamates, oxamides, oxanilides, benzoxazinones, orbenzoxazoles.

In a preferable embodiment, examples of the radical scavenger group orthe ultraviolet ray absorbing group include:

In this embodiment, X¹, X⁵ and X¹ may be each independently a 3-10valent organic group.

In the formula, t is each independently an integer of 1-10. In apreferable embodiment, t is an integer of 1-6. In another preferableembodiment, t is an integer of 2-10, preferably an integer of 2-6.

In the formula, X² is each independently at each occurrence a singlebond or a divalent organic group. X² is preferably an alkylene grouphaving 1-20 carbon atoms, more preferably —(CH₂)_(u)— wherein u is aninteger of 0-2.

The preferable compound of the formulae (A1) and (A2) is a compound ofthe formula (A1′) and (A2′):

wherein:

PFPE is each independently a group of the formula:

—(OC₄F₈)_(a)—(OC₃F₆)_(b)—(OC₂F₄)—(OCF₂)₄—

wherein a, b, c and d are each independently an integer of 0-200, thesum of a, b, c and d is one or more, and the occurrence order of therespective repeating units in parentheses with the subscript a, b, c ord is not limited in the formula,

Rf is each independently at each occurrence an alkyl group having 1-16carbon atoms which may be substituted by one or more fluorine atoms;

R¹ is each independently at each occurrence a hydrogen atom or an alkylgroup having 1-22 carbon atoms;

R² is each independently at each occurrence a hydroxyl group or ahydrolyzable group;

R¹¹ is each independently at each occurrence a hydrogen atom or ahalogen atom;

R¹² is each independently at each occurrence a hydrogen atom or a loweralkyl group;

n is an integer of 0-2, preferably 0;

X is —O—CFR¹³—(CF₂)_(e)—;

R¹³ is a fluorine atom or a lower fluoroalkyl group;

e is 0 or 1;

X² is —(CH₂)_(u)—;

u is an integer of 0-2 (when u is 0, X² is a single bond); and

t is an integer of 1-10.

The compound of the formulae (A1) and (A2) can be obtained for exampleby introducing an iodine into in the end of a perfluoropolyetherderivative corresponding to the Rf—PFPE moiety as a raw material, andthen reacting it with a vinyl monomer corresponding to —CH₂CR¹²(X²—SiR¹_(n)R² _(3-n))—.

Formulae (B1) and (B2):

(Rf—PFPE)_(β′)—X⁵—(SiR¹ _(n)R² _(3-n))_(β)  (B1)

(R² _(3-n)R¹ _(n)Si)_(β)X⁵—PFPE-X⁵—(SiR¹ _(n)R² _(3-n))_(β)  (B2)

In the formulae (B1) and (B2), Rf, PFPE, R¹, R² and n are as definedabove for the formulae (A1) and (A2).

In the formula, X⁵ is each independently a single bond or a 2-10 valentorganic group. X⁵ is recognized to be a linker which connects between aperfluoropolyether moiety (i.e., an Rf—PFPE moiety or —PFPE- moiety)providing mainly water-repellency, surface slip property and the likeand a silane moiety (specifically, —SiR¹ _(n)R² _(3-n)) providing anability to bind to a base material in the compound of the formulae (B1)and (B2). Therefore, X⁵ may be any organic group as long as the compoundof the formula (B1) and (B2) can stably exist.

In the formula, β is an integer of 1-9, and β′ is an integer of 1-9. βand β′ may be determined depending on the valence number of X⁵, and inthe formula (B1), the sum of β and β′ is the valence number of X⁵. Forexample, when X⁵ is a 10 valent organic group, the sum of β and β′ is10, for example, β is 9 and β′ is 1, β is 5 and β′ is 5, or β is 1 andβ′ is 9. When X⁵ is a divalent organic group, P and β′ are 1. In theformula (B2), β is a value obtained by subtracting 1 from the valencenumber of X⁵.

X⁵ is preferably a 2-7 valent, more preferably a 2-4 valent, furtherpreferably a divalent organic group.

In one embodiment, X⁵ is a 2-4 valent organic group, P is 1-3, and β′ is1.

In another embodiment, X⁵ is a divalent organic group, β is 1, and β′is 1. In this case, the formulae (B1) and (B2) are represented by thefollowing formulae (B1) and (B2′).

Rf—PFPE-X⁵—SiR¹ _(n)R² _(3-n)  (B1)

R² _(3-n)R¹ _(n)Si—X⁵—PFPE-X⁵—SiR¹ _(n)R² _(3-n)  (B2′)

Examples of X⁵ include, but are not particularly limited to, forexample, the same group as those described for X¹.

Among them, a preferable specific embodiment of X⁵ includes:

—CH₂O(CH₂)₂,—CH₂O(CH₂)₃—,—CH₂O(CH₂)₆—,—CH₂O(CH₂)₃Si(CH₃)₂OSi(CH₃)₂(CH₂)₂—,—CH₂O(CH₂)₃Si(CH₃)₂OSi(CH₃)₂OSi(CH₃)₂(CH₂)₂—,—CH₂O(CH₂)₃Si(CH₃)₂O(Si(CH₃)₂O)₂Si(CH₃)₂(CH₂)₂—,—CH₂O(CH₂)₃Si(CH₃)₂O(Si(CH₃)₂O)₃Si(CH₃)₂(CH₂)₂—,—CH₂O(CH₂)₃Si(CH₃)₂O(Si(CH₃)₂O)₁₀Si(CH₃)₂(CH₂)₂-r—CH₂O(CH₂)₃Si(CH₃)₂O(Si(CH₃)₂O)₂₀Si(CH₃)₂(CH₂)₂—,—CH₂OCF₂CHFOCF₂—,—CH₂OCF₂CHFOCF₂CF₂—,—CH₂OCF₂CHFOCF₂CF₂CF₂—,—CH₂OCH₂CF₂CF₂OCF₂—,—CH₂OCH₂CF₂CF₂)OCF₂CF₂—,—CH₂OCH₂CF₂CF₂)OCF₂CF₂CF₂—,—CH₂OCH₂CF₂CF₂OCF(CF₃) CF₂OCF₂—,—CH₂OCH₂CF₂CF₂OCF(CF₃) CF₂OCF₂CF₂—,—CH₂OCH₂CF₂CF₂OCF(CF₃)CF₂OCF₂CF₂CF₂—,—CH₂OCH₂CHFCF₂OCF₂—,—CH₂OCH₂CHFCF₂)OCF₂CF₂—,—CH₂OCH₂CHFCF₂)OCF₂CF₂CF₂—,—CH₂OCH₂CHFCF₂OCF(CF₃) CF₂OCF₂—,—CH₂OCH₂CHFCF₂OCF(CF₃)₂OCF₂F₂OCF₂CF₂—,—CH₂OCH₂CHFCF₂OCF(CF₃) CF₂OCF₂CF₂CF₂—-CH₂OCH₂(CH₂)₇CH₂Si(OCH₃)₂OSi(OCH₃)₂(CH₂)₂Si(OCH₃)₂OSi(OCH₃)₂(CH₂)₂—,—CH₂OCH₂CH₂CH₂Si(OCH₃)₂OSi(OCH₃)₂(CH₂)₃—,—CH₂OCH₂CH₂CH₂Si(OCH₂CH₃)₂OSi(CH₂CH₃)₂(CH₂)₃—,—CH₂OCH₂CH₂Si(OCH₃)₂OSi(OCH₃)₂(CH₂)₂—,—CH₂OCH₂CH₂CH₂Si(OCH₂CH₃)₂Si(OCH₂CH₃)₂(CH₂)₂—,—(CH₂)₂—,—(CH₂)₃—,—(CH₂)₄—,—(CH₂)₆—,—(CH₂)₂—Si(CH₃)₂(CH₂)₂—,—CONH—(CH₂)₃—,—CON(CH₃)—(CH₂)₃—,—CON(Ph)-(CH₂)₃— (wherein Ph is phenyl),—CONH—(CH₂)₆—,—CON(CH₃)—(CH₂)₆,—CON(Ph)-(CH₂)₆— (wherein Ph is phenyl),—CONH—(CH₂)₂NH(CH₂)₃—,—CONH—(CH₂)₆NH(CH₂)₃)—CH₂O—CONH—(CH₂)₃—,—CH₂O—CONH—(CH₂)₆—,—S—(CH₂)₃—,—(CH₂)₂S(CH₂)₃—,—CONH—(CH₂)₃Si(CH₃)₂OSi(CH₃)₂(CH₂)₂—,—CONH—(CH₂)₃Si(CH₃)₂OSi(CH₃)₂OSi(CH₃)₂(CH₂)₂—,—CONH—(CH₂)₃Si(CH₃)₂O(Si(CH₃)₂O)₂Si(CH₃)₂(CH₂)₂—,—CONH—(CH₂)₃Si(CH₃)₂O(Si(CH₃)₂O)₃Si(CH₃)₂(CH₂)₂—,—CONH—(CH₂)₃Si(CH₃)₂O(Si(CH₃)₂O)₁₀Si(CH₃)₂(CH₂)₂—,—CONH—(CH₂)₃Si(CH₃)₂O(Si(CH₃)₂O)₂₀Si(CH₃)₂(CH₂)₂—,—C(O)O—(CH₂)₃—,—C(O)O—(CH₂)₆—,—CH₂—O—(CH₂)₃—Si(CH₃)₂—(CH₂)₂—Si(CH₃)₂—(CH₂)₂—,—CH₂—O—(CH₂)₃—Si(CH₃)₂—(CH₂)₂—Si(CH₃)₂—CH(CH₃)₂—,—CH₂—O—(CH₂)₃—Si(CH₃)₂—(CH₂)₂—Si(CH₃)₂—(CH₂)₃—,—CH₂—O—(CH₂)₃—Si(CH₃)₂—(CH₂)₂—Si(CH₃)₂—CH(CH₃)—CH₂—,

The preferable compound of the formulae (B1) and (B2) is a compound ofthe formula (B1′) and (B2′):

Rf—PFPE-X⁵—SiR¹ _(n)R² _(3-n)  (B1′)

R² _(3-n)R¹ _(n)Si—X⁵—PFPE-X⁵—SiR¹ _(n)R² _(3-n)  (B2′)

wherein:

PFPE is each independently a group of the formula:

—(OC₄F₈)_(a)—(OC₃F₆)_(b)—(OC₂F₄)_(c)—(OCF₂)_(d)—

wherein a, b, c and d are each independently an integer of 0-200, thesum of a, b, c and d is one or more, and the occurrence order of therespective repeating units in parentheses with the subscript a, b, c ord is not limited in the formula,

Rf is each independently at each occurrence an alkyl group having 1-16carbon atoms which may be substituted by one or more fluorine atoms;

R¹ is each independently at each occurrence a hydrogen atom or an alkylgroup having 1-22 carbon atoms;

R² is each independently at each occurrence a hydroxyl group or ahydrolyzable group;

n is an integer of 0-2, preferably 0; and

X⁵ is —CH₂O(CH₂)₂—, —CH₂O(CH₂)₃— or CH₂O(CH₂)₆—.

The compound of the formulae (B1) and (B2) can be prepared by a knownmethod, for example, a method described in Patent Document 1 or themodified method thereof. For example, the compound of the formulae (B1)and (B2) can be prepared by reacting a compound of the formula (B1-4) or(B2-4):

(Rf—PFPE)_(β′)—X^(5′)—(R⁸²—CH═CH₂)_(β)  (B1-4)

(CH₂═CH—R⁸²)_(β)—X^(5′)—PFPE-X^(5′)—R⁸²—CH═CH₂)_(β)  (B2-4)

wherein:

PFPE is each independently a group of the formula:

—(OC₄F₈)_(a)—(OC₃F₆)_(b)—(OC₂F₄)_(c)—(OCF₂)_(d)—

wherein a, b, c and d are each independently an integer of 0-200, thesum of a, b, c and d is one or more, and the occurrence order of therespective repeating units in parentheses with the subscript a, b, c ord is not limited in the formula,

Rf is each independently at each occurrence an alkyl group having 1-16carbon atoms which may be substituted by one or more fluorine atoms;

X^(5′) is each independently a single bond or a 2-10 valent organicgroup;

β is each independently an integer of 1-9;

β′ is each independently an integer of 1-9; and

R⁸² is a single bond or a divalent organic group, with HSiM₃ wherein Mis each independently a halogen atom, R¹ or R², R¹ is each independentlyat each occurrence a hydrogen atom or an alkyl group having 1-22 carbonatoms, and R² is each independently at each occurrence a hydroxyl groupor a hydrolyzable group, and

as necessary, converting the halogen atom to R¹ or R², as a compound ofthe formula (B1″) or (B2″):

(Rf—PFPE)_(β′)—X^(5′)—(R⁸²—CH₂CH₂—SiR¹ _(n)R² _(3-n))_(β)  (B1″)

(R¹ _(n)R² _(3-n)Si—CH₂CH₂—R⁸²)_(β)X^(5′)—PFPE-X⁵—**(R⁸²—CH₂CH₂—SiR¹_(n)R² _(3-n))_(β)  (B2″)

wherein PFPE, Rf, X^(5′), β, β′ and R⁸² are as defined above; and

n is an integer of 0-3.

In the formula (B1″) or (B2″), the portion from X^(5′) to R⁸²—CH₂CH₂—corresponds to X⁵ in the formula (B1) or (B2). Therefore, the preferableX^(5′) is a group excluding a portion corresponding to —R⁸²—CH₂CH₂— fromthe preferable X⁵ described above.

Formulae (C1) and (C2):

(Rf—PFPE)_(γ)—X⁷—(SiR^(a) _(k)R^(b) _(l)R^(c) _(m))_(γ)  (C1)

(R^(c) _(m)R^(b) _(l)R^(a) _(k)Si)_(γ)—X⁷—PFPE-X⁷—(SiR^(a) _(k)R^(b)_(l)R^(c) _(m))_(γ)  (C2)

In the formulae (C1) and (C2), Rf and PFPE are as defined for theformulae (A1) and (A2)

In the formula, X⁷ is each independently a single bond or a 2-10 valentorganic group. X⁷ is recognized to be a linker which connects between aperfluoropolyether moiety (an Rf—PFPE moiety or —PFPE- moiety) providingmainly water-repellency, surface slip property and the like and a silanemoiety (specifically, —SiR^(a) _(k)R^(b) _(l)R^(c) _(m)) providing anability to bind to a base material in the compound of the formula (C1)and (C2). Therefore, X⁷ may be any organic group as long as the compoundof the formula (C1) and (C2) can stably exist.

In the formula, γ is an integer of 1-9, and γ′ is an integer of 1-9. γand γ′ may be determined depending on the valence number of X⁷, and inthe formula (C1), the sum of γ and γ′ is the valence number of X⁷. Forexample, when X⁷ is a 10 valent organic group, the sum of γ and γ′ is10, for example, γ is 9 and γ′ is 1, γ is 5 and γ′ is 5, or γ is 1 andγ′ is 9. When X⁷ is a divalent organic group, γ and γ′ are 1. In theformula (C1), γ is a value obtained by subtracting 1 from the valencenumber of X⁷.

X⁷ is preferably a 2-7 valent, more preferably a 2-4 valent, furtherpreferably a divalent organic group.

In one embodiment, X⁷ is a 2-4 valent organic group, γ is 1-3, and γ′ is1.

In another embodiment, X⁷ is a divalent organic group, γ is 1, and γ′is 1. In this case, the formulae (C1) and (C2) are represented by thefollowing formulae (C1′) and (C2′).

Rf—PFPE-X⁷—SiR^(a) _(k)R^(b) _(l)R^(c) _(m)  (C1′)

R^(c) _(m)R^(b) _(l)R^(a) _(k)Si—X⁷—PFPE-X⁷—SiR^(a) _(k)R^(b) _(l)R^(c)_(m)  (C2′)

Examples of X⁷ include, but are not particularly limited to, forexample, the same groups as those described for X¹.

Among them, a preferable specific embodiment of X⁷ includes:

—CH₂O(CH₂)₂—,—CH₂O(CH₂)₃—,—CH₂O(CH₂)₆—,—CH₂O(CH₂)₃Si(CH₃)₂OSi(CH₂)₂(CH₂)₂—,—CH₂O(CH₂)₃Si(CH₃)₂OSi(CH₃)₂OSi(CH₃)₂(CH₂)₂—,—CH₂O(CH₂)₃Si(CH₂)₂O(Si(CH₃)₂O)₂Si(CH)₂(CH₂)₂—,—CH₂O(CH₂)₃Si(CH₃)₂O(Si(CH₃)₂O)₃Si(CH)₂(CH₂)₂—,—CH₂O(CH₂)₃Si(CH₃)₂O(Si(CH₃)₂O), Si(CH₃)₂(CH₂)₂—,—CH₂O(CH₂)₃Si(CH₃)₂O(Si(CH₃)₂O)₂₀Si(CH₃)₂(CH₂)₂—,—CH₂OCF₂CHFOCF₂—,—CH₂OCF₂CHFOCF₂CF₂—,—CH₂OCF₂CHFOCF₂CF₂CF₂—,—CH₂OCH₂CF₂CF₂OCF₂—,—CH₂OCH₂CF₂CF₂OCF₂CF₂—,—CH₂OCH₂CF₂CF₂OCF₂CF₂CF₂—,—CH₂OCH₂CF₂CF₂OCF(CF₃)CF₂CF₂—,—CH₂OCH₂CF₂CF₂OCF(CF₃) F₂OCF₂CF₂—,—CH₂OCH₂CF₂CF₂OCF(CF₃)CF₂OCF₂CF₂CF₂—,—CH₂OCH₂CHFCF₂OCF₂—,—CH₂OCH₂CHFCF₂OCF₂CF₂—,—CH₂OCH₂CHFCF₂OCF₂CF₂CF₂—,—CH₂OCH₂CHFCF₂OCF(CF₃)CF₂OCF₂—,—CH₂OCH₂CHFCF₂OCF(CF₃) CF₂OCF₂CF₂—,—CH₂OCH₂CHFCF₂OCF(CF₃) CF₂OCF₂CF₂CF₂—-CH₂OCH₂(CH₂)₇CH₂Si(OCH₃)₂OSi(OCH)₂(CH₂)₂Si(OCH₃)₂OSi(OCH₃)₂(CH₂)₂—,—CH₂OCH₂CH₂CH₂Si(OCH₃)₂OSi(OCH₃)₂(CH₂)₃—,—CH₂OCH₂CH₂CH₂Si(OCH₂CH₃)₂OSi(OCH₃)₂(CH₃)₂(CH₂)₃—,—CH₂OCH₂CH₂CH₂Si(OCH₃)₂OSi(OCH₃)₂(CH₂)₂—,—CH₂OCH₂CHCH₂Si(OCH₂CH₃)₂OSi(OCH₂CH₃)₂(CH₂)₂—,—(CH₂)₂—,—(CH₂)₃—,S(CH₂)₄—,—(CH₂)₆—,—(CH₂)₂—Si(CH₃)₂—(CH₂)₂——CONH—(CH₂)₃—,—CON(CH₃)—(CH₂)₃—,—CON(Ph)-(CH₂)₃— (wherein Ph is phenyl),—CONH—(CH₂)₆—,—CON(CH₃)—(CH₂)₆—,—CON(Ph)-(CH₂)₆— (wherein Ph is phenyl),—CONH—(CH₂)₂NH(CH₂)₃—,—CONH—(CH₂)₆NH(CH₂)₃——CH₂O—CONH—(CH₂)₃—,—CH₂O—CONH—(CH₂)₆—,—S—(CH₂)₃—,—(CH₂)₂S(CH₂)₃,—CONH—(CH₂)₃Si(CH₃)₂OSi(CH₃)₂(CH₂)₂—,—CONH—(CH₂)₃Si(CH₃)₂OSi(CH₃)₂OSi(CH₃)₂(CH₂)₂—,—CONH—(CH₂)₃Si(CH₃)₂O(Si(CH₃)₂O)₂Si(CH₃)₂(CH₂)₂—,—CONH—(CH₂)₃Si(CH₃)₂O(Si(CH₃)₂O)₃Si(CH₃)₂(CH₂)₂,—CONH—(CH₂)₃Si(CH₃)₂O(Si(CH₃)₂O) Si(CH₃)₂(CH₂)₂—,—CONH—(CH₂)₃Si(CH₃)₂O(Si(CH₃)₂O)₂OSi(CH₃)₂(CH₂)₂——C(O)O—(CH₂)₃—,—C(O)O—(CH₂)₆—,—CH—O—(CH₂)₃—Si(CH₃)₂—(CH₂)₂—Si(CH₃)₂(CH₂)₂—,—CH₂—O—(CH₂)₃—Si(CH₃)₂—(CH₂)—Si(CH₃₂—CH(CH₃)₂—,—CH₂—O—(CH₂)₃—Si(CH₃)—(CH₂)₂—Si(CH₃)₂(CH₂)₃—CH₂—O—(CH₂)₃—Si(CH₃)₂—(CH₂)₂—Si(CH₃)₂—CH(CH₃)—CH₂—,

In the formula, R^(a) is each independently at each occurrence —Z—SiR⁷¹_(p)R⁷² _(q)R⁷³ _(r).

In the formula, Z is each independently at each occurrence an oxygenatom or a divalent organic group.

Z is preferably a divalent organic group, and does not include a groupwhich forms a siloxane bond together with a Si atom (the Si atom bindingto R^(a)) present in the end of the molecular backbone of the formula(C1) or the formula (C2).

Z is preferably a C₁₋₆ alkylene group, —(CH₂)_(g)—O—(CH₂)_(h)— (whereing is an integer of 1-6, h is an integer of 1-6) or -phenylene-(CH₂)_(i)—(wherein i is an integer of 0-6), more preferably a C₁₋₃ alkylene group.These groups may be substituted with, for example, one or moresubstituents selected form a fluorine atom, a C₁₋₆ alkyl group, a C₂₋₆alkenyl group, and a C₂₋₆ alkynyl group.

In the formula, R⁷¹ is each independently at each occurrence R^(a′),R^(a′) is as defined for R^(a).

In R^(a), the number of Si atoms which are linearly connected via Z isup to five. That is, in R^(a), when there is at least one R⁷¹, there aretwo or more Si atoms which are linearly connected via Z in R^(a). Thenumber of such Si atoms which are linearly connected via Z is five atmost. It is noted that “the number of such Si atoms which are linearlyconnected via Z in R^(a) is equal to the repeating number of —Z—Si—which are linearly connected in R^(a).

For example, one example in which Si atoms are connected via Z in R^(a)is shown below.

in the above formula, * represents a position binding to Si of the mainbackbone, and . . . represents that a predetermined group other than ZSibinds thereto, that is, when all three bonds of a Si atom are . . . , itmeans an end point of the repeat of ZSi. The number on the rightshoulder of Si means the number of occurrences of Si which is linearlyconnected via the Z group from *. In other words, in the chain in whichthe repeat of ZSi is completed at Si², “the number of such Si atomswhich are linearly connected via the Z group in R^(a)” is 2. Similarly,in the chain in which the repeat of ZSi is completed at Si³, Si⁴ andSi⁵, respectively, “the number of such Si atoms which are linearlyconnected via the Z group in R^(a)” is 3, 4 and 5. It is noted that asseen from the above formula, there are some ZSi chains, but they neednot have the same length and may be have arbitrary length.

In a preferred embodiment, as shown below, “the number of such Si atomswhich are linearly connected via the Z group in R^(a)” is 1 (leftformula) or 2 (right formula) in all chains.

In one embodiment, the number of such Si atoms which are linearlyconnected via the Z group in R^(a) is 1 or 2, preferably 1.

In the formula, R⁷² is each independently at each occurrence a hydroxylgroup or a hydrolyzable group.

The “hydrolyzable group” as used herein represents a group which is ableto undergo a hydrolysis reaction. Examples of the hydrolyzable groupinclude —OR, —OCOR, —O—N═C(R)₂, —N(R)₂, —NHR, halogen (wherein R is asubstituted or non-substituted alkyl group having 1-4 carbon atoms),preferably —OR (an alkoxy group). Examples of R include anon-substituted alkyl group such as a methyl group, an ethyl group, apropyl group, an isopropyl group, a n-butyl group, an isobutyl group; asubstituted alkyl group such as a chloromethyl group. Among them, analkyl group, in particular a non-substituted alkyl group is preferable,a methyl group or an ethyl group is more preferable. The hydroxyl groupmay be, but is not particularly limited to, a group generated byhydrolysis of a hydrolyzable group.

Preferably, R⁷² is —OR wherein R is a substituted or unsubstituted C₁₋₃alkyl group, more preferably a methyl group.

In the formula, R⁷³ is each independently at each occurrence a hydrogenatom or a lower alkyl group. The lower alkyl group is preferably analkyl group having 1-20 carbon atoms, more preferably an alkyl grouphaving 1-6 carbon atoms, further preferably a methyl group.

In the formula, p is each independently at each occurrence an integer of0-3; q is each independently at each occurrence an integer of 0-3; and ris each independently at each occurrence an integer of 0-3. The sum ofp, q and r is 3.

In a preferable embodiment, in R^(a′) at the end of R^(a) (R^(a) whenR^(a′) is absent), q is preferably 2 or more, for example, 2 or 3, morepreferably 3.

In a preferable embodiment, at least one of the end portions in R^(a)may be —Si(—Z—SiR⁷² _(q)R⁷³)₂ or —Si(—Z—SiR⁷² _(q)R⁷³ _(r))₃, preferably—Si(—Z—SiR⁷² _(q)R⁷³ _(r))₃. In the formula, the unit (—Z—SiR⁷² _(q)R⁷³_(r)) is preferably (—Z—SiR⁷² ₃). In a further preferable embodiment,all end portions in R^(a) may be —Si(—Z—SiR⁷² _(q)R⁷³ _(r))₃, preferably—Si(—Z—SiR⁷² ₃)₃.

In the formulae (C1) and (C2), at least one R⁷² is present.

In the formula, R^(b) is each independently at each occurrence ahydroxyl group or a hydrolyzable group.

R^(b) is preferably a hydroxyl group, —OR, —OCOR, —O—N═C(R)₂, —N(R)₂,—NHR, halogen (wherein R is a substituted or unsubstituted alkyl grouphaving 1-4 carbon atoms), more preferably —OR. R is an unsubstitutedalkyl group such as a methyl group, an ethyl group, a propyl group, anisopropyl group, a n-butyl group, an isobutyl group; a substituted alkylgroup such as a chloromethyl group. Among them, an alkyl group, inparticular unsubstituted alkyl group is preferable, and a methyl groupor an ethyl group is more preferable. The hydroxyl group may be, but isnot particularly limited to, a group generated by hydrolysis of ahydrolyzable group. More preferably, R^(c) is —OR wherein R is asubstituted or unsubstituted C₁₋₃ alkyl group, more preferably a methylgroup.

In the formula, R^(c) is each independently at each occurrence ahydrogen atom or a lower alkyl group. The lower alkyl group ispreferably an alkyl group having 1-20 carbon atoms, more preferably analkyl group having 1-6 carbon atoms, further preferably a methyl group.

In the formula, k is each independently at each occurrence an integer of0-3; l is each independently at each occurrence an integer of 0-3; m iseach independently at each occurrence an integer of 0-3. The sum of k, land m is 3.

The compound of the formulae (C1) and (C2) can be prepared, for example,by introducing a hydroxyl group in the end of a perfluoropolyetherderivative corresponding to the Rf—PFPE moiety as a raw material,followed by further introducing a group having an unsaturated group inthe end thereof, and reacting the group having an unsaturated group witha silyl derivative having a halogen atom, further introducing a hydroxylgroup in the end of the silyl group, and then reacting the group havingan unsaturated group with a silyl derivative. For example, the compoundcan be prepared as follows.

The preferable compound of the formulae (C1) and (C2) a compound of thefollowing formulae (C1″) and (C2″):

Rf—PFPE-X⁷—SiR^(a) ₃  (C1′)

R^(a) ₃Si—X⁷—PFPE-X⁷—SiR^(a) ₃  (C2′)

wherein:

PFPE is each independently a group of the formula:

—(OC₄F₈)_(a)—(OC₃F₆)_(b)—(OC₂F₄)_(c)—(CF₂)_(d)—

wherein a, b, c and d are each independently an integer of 0-200, thesum of a, b, c and d is 1 or more, and the occurrence order of therespective repeating units in parentheses with the subscript a, b, c ord is not limited in the formula;

Rf is each independently at each occurrence an alkyl group having 1-16carbon atoms which may be substituted by one or more fluorine atoms;

X⁷ is —CH₂O(CH₂)₂—, —CH₂O(CH₂)₃— or —CH₂O(CH₂)₆—;

R^(a) is each independently at each occurrence —Z—SiR⁷¹ _(p)R⁷² _(q)R⁷³_(r);

Z is a C₁₋₆ alkylene group;

R⁷¹ is each independently at each occurrence R^(a′);

R^(a′) has the same definition as that of R^(a);

in R^(a) the number of Si atoms which are straightly linked via the Zgroup is up to five;

R⁷² is each independently at each occurrence a hydroxyl group or ahydrolyzable group;

R⁷³ is each independently at each occurrence a hydrogen atom or a loweralkyl group;

p is each independently at each occurrence an integer of 0-2;

q is each independently at each occurrence an integer of 1-3, preferably3;

r is each independently at each occurrence an integer of 0-2; and

in one R^(a), the sum of p, q and r is 3.

In the compound of the formulae (C1) and (C2), for example, thefollowing formulae (C1-4) or (C2-4):

(Rf—PFPE)_(γ′)—X^(7′)—(R⁸²—CH═CH₂)  (C1-4)

(CH₂CH—R⁸²)_(γ)—X^(7′)—PFPE-X^(7′)—(R⁸²—CH═CH₂)_(γ)  (C2-4)

wherein:

PFPE is each independently a group of the formula:

—(OC₄F₈)_(a)—(OC₃F₆)_(b)—(OC₂F₄)_(c)—(OCF₂)_(d)—

wherein a, b, c and d are each independently an integer of 0-200, thesum of a, b, c and d is 1 or more, and the occurrence order of therespective repeating units in parentheses with the subscript a, b, c ord is not limited in the formula;

Rf is each independently at each occurrence an alkyl group having 1-16carbon atoms which may be substituted by one or more fluorine atoms;

X^(7′) is each independently a single bond or a 2-10 valent organicgroup;

γ is each independently an integer of 1-9;

γ′ is each independently an integer of 1-9; and

R⁸² is a single bond or a divalent organic group, is reacted with acompound of HSiR⁸³ _(k)R^(b) _(l)R^(c) _(m) wherein R⁸³ is a halogenatom, for example a fluorine atom, a chlorine atom, a bromine atom or aniodine atom, preferably a chlorine atom, R^(b) is each independently ateach occurrence a hydroxyl group or a hydrolyzable group, R^(c) is eachindependently at each occurrence a hydrogen atom or a lower alkyl group,k is an integer of 1-3, l and m are each independently an integer of0-2, and the sum of k, l and m is 3,

to obtain a compound of the formula (C1-5) or (C2-5):

(Rf—PFPE)_(γ′)—X^(7′)—(R⁸²—CH₂CH₂—SiR⁸³ _(k)R^(b) _(l)R^(c)_(m))_(γ)  (C1-5)

(R^(c) _(m)R^(b) _(l)R⁸³_(k)Si—CH₂CH₂—R⁸²)_(γ)—X^(7′)—PFPE-**X^(7′)—(R⁸²—CH₂CH₂—SiR⁸³ _(k)R^(b)_(l)R^(c) _(m))_(γ)  (C2-5)

wherein Rf, PFPE, R⁸², R⁸³, R^(b), R^(c), γ, γ′, X⁷, k, l and m are asdefined above.

The compound of the formula (C1-5) or (C2-5) obtained is reacted with acompound of Hal-J-R⁸⁴—CH═CH₂ wherein Hal is a halogen atom (for example,I, Br, Cl, F, or the like), J is Mg, Cu, Pd or Zn, and R⁸⁴ is a singlebond or a divalent organic group,

to obtain a compound of the formula (C1-6) or (C2-6):

(Rf—PFPE)_(γ′)—X^(7′)—(R⁸²—CH₂CH₂—SiR^(b) _(l)R^(c)_(m)(R⁸⁴—CH═CH₂)_(k))_(γ)  (C1-6)

((CH═CH₂—R⁸⁴ _(k)R^(c) _(m)R^(b)_(l)Si—CH₂CH₂—R⁸²)_(γ)—X^(7′)—PFPE-**X^(7′)—(R⁸²—CH₂CH₂—SiR^(b)_(l)R^(c) _(m)(R⁸⁴—CH═CH₂)_(k))_(γ)  (C2-5)

wherein Rf, PFPE, R⁸², R⁸⁴, R^(b), R^(c), γ, γ′, X⁷, k, l and m are asdefined above.

The compound of the formula (C1-6) or (C2-6) obtained can be reactedwith HSiM₃ (wherein M is each independently a halogen atom, R⁷² or R⁷³,R⁷² is each independently at each occurrence a hydroxyl group or ahydrolyzable group, and R⁷³ is each independently at each occurrence ahydrogen atom or a lower alkyl group), and as necessary, converting thehalogen atom the halogen atom to R⁷² or R⁷³ to obtain a compound of theformula (C1′″) or (C2′″):

(Rf—PFPE)_(γ′)—X^(7′)—(R⁸²—CH₂CH₂—SiR^(b) _(l)R^(c)_(m)(R⁸⁴—CH₂CH₂—SiR⁷² _(q)R⁷³ _(r))_(k))_(γ)  (C1′″)

((R⁷² _(q)R⁷³ _(r)Si—CH₂CH₂—R⁸⁴)_(k)R^(c) _(m)R^(b)_(l)Si—CH₂CH₂—R⁸²)_(γ)—X^(7′)—PFPE-**X^(7′)—(R⁸²—CH₂CH₂—SiR^(b)_(l)R^(c) _(m)(R⁸⁴—CH₂CH₂—SiR⁷² _(q)R⁷³ _(r))_(k))_(γ)  (C2-5)

wherein

Rf, PFPE, R⁷², R⁷³, R⁸², R⁸⁴, R^(b), R^(c), γ, γ′, X^(7′), k, l and mare as defined above;

q is each independently at each occurrence an integer of 1-3; and

r is each independently at each occurrence an integer of 0-2.

In the formula (C1′″) or (C2′″), a portion from X^(7′) to R⁸²—CH₂CH₂—corresponds to X⁷ in the formula (C1) or (C2), and —R⁸⁴—CH₂CH₂—corresponds to Z in the formula (C1) or (C2).

In the surface-treating agent of the present invention, a proportion ofthe perfluoro(poly)ether group containing silane compound having amolecular weight of 3,000 or less in the perfluoro(poly)ether groupcontaining silane compounds of the above formula (A1), (A2), (B1), (B2),(C1) or (C2) is 9 mol % or less, preferably 7 mol % or less, furtherpreferably 5 mol % or less. By setting the proportion of theperfluoro(poly)ether group containing silane compound having a molecularweight of 3,000 or less to 9 mol % or less, the surface-treating layerhaving more excellent friction durability can be formed. It is notedthat the proportion is a proportion of the perfluoro(poly)ether groupcontaining silane compound having a molecular weight of 3,000 or lesswith respect to the total amount of the perfluoro(poly)ether groupcontaining silane compounds of the above general formulae contained inthe surface-treating agent of the present invention.

A method of adjusting the proportion of the perfluoro(poly)ether groupcontaining silane compound having a molecular weight of 3,000 or lesswith respect to the whole of the perfluoro(poly)ether group containingsilane compounds contained in the surface-treating agent to 9 mol % orless is not particularly limited, and includes, for example, a methodthat the compounds having low molecular weight is removed bydistillation, etc. The distillation is preferably a moleculardistillation. The distillation may be performed for theperfluoro(poly)ether group containing silane compound, or a rawmaterial, for example, an acid fluoride having a perfluoropolyethergroup. The condition of the distillation can be selected depending on acompound to be distilled by those skilled in the art.

The proportion of the perfluoro (poly)ether group containing silanecompound having a molecular weight of 3,000 or less with respect to thewhole of the perfluoro(poly)ether group containing silane compoundscontained in the surface-treating agent can be measured by GPC (GelPermeation Chromatography) analysis. The GPC measurement can beperformed for example by using GPCmax provided with TDA-302(HPLC system:manufactured by Malvern Instruments) as a detector.

The number average molecular weight of the perfluoro(poly)ether groupcontaining silane compound contained in the surface-treating agent ofthe present invention is preferably 5,000 or more, more preferably 6,000or more, preferably 100,000 or less, more preferably 30,000 or less,further preferably 10,000 or less.

The number average molecular weight of the PFPE portion of theperfluoro(poly)ether group containing silane compound contained in thesurface-treating agent of the present invention may be, not particularlylimited to, preferably 4,000-30,000, more preferably 5,000-10,000.

In the present invention, the “number average molecular weight” ismeasured by GPC (Gel Permeation Chromatography) analysis.

The surface-treating agent of the present invention can provide a basematerial with water-repellency, oil-repellency, antifouling property,waterproof property and high friction durability, and can be suitablyused as an antifouling-coating agent or a water-proof coating agent,although the present invention is not particularly limited thereto.

The surface treating agent may be diluted with a solvent. Examples ofthe solvent include, but are not particularly limited to, for example, asolvent selected from the group consisting of perfluorohexane,CF₃CF₂CHCl₂, CF₃CH₂CF₂CH₃, CF₃CHFCHFC₂F₅,1,1,1,2,2,3,3,4,4,5,5,6,6-tridecafluorooctane,1,1,2,2,3,3,4-heptafluorocyclopentane (ZEORORA H (trade name), etc.),C₄F₉OCH₃, C₄F₉OC₂H₅, CF₃CH₂OCF₂CHF₂, C₆F₁₃CH═CH₂, xylene hexafluoride,perfluorobenzene, methyl pentadecafluoroheptyl ketone, trifluoroethanol,pentafluoropropanol, hexafluoroisopropanol, HCF₂CF₂CH₂OH, methyltrifluoromethanesulfonate, trifluoroacetic acid andCF₃O(CF₂CF₂O)_(m)(CF₂O)_(n)CF₂CF₃ [wherein m and n are eachindependently an integer of 0 or more and 1000 or less, the occurrenceorder of the respective repeating units in parentheses with thesubscript m or n is not limited in the formula, with the proviso thatthe sum of m and n is 1 or more.],1,1-dichloro-2,3,3,3-tetrafluoro-1l-propene,1,2-dichloro-1,3,3,3-tetrafluoro-1-propene,1,2-dichloro-3,3,3-trichloro-1-propene,1,1-dichloro-3,3,3-trichloro-1-propene,1,1,2-trichloro-3,3,3-trichloro-1-propene,1,1,1,4,4,4-hexafluoro-2-butene. These solvents may be used alone or asa mixture of 2 or more compound.

The surface treating agent may comprise other components in addition tothe perfluoro(poly)ether group containing silane compound. Examples ofthe other components include, but are not particularly limited to, forexample, a (non-reactive) fluoropolyether compound which may be alsounderstood as a fluorine-containing oil, preferably aperfluoro(poly)ether compound (hereinafter, referred to as “thefluorine-containing oil”), a (non-reactive) silicone compound which maybe also understood as a silicone oil (hereinafter referred to as “asilicone oil”), a catalyst, and the like.

Examples of the above-mentioned fluorine-containing oil include, but arenot particularly limited to, for example, a compound of the followinggeneral formula (3) (a perfluoro(poly)ether compound).

Rf¹—(OC₄F₈)_(a′)—(OC₃F₆)_(b′)—(OC₂F₄)_(c′)—(OCF₂)_(d′)—Rf²  (3)

In the formula, Rf¹ is a C₁₋₁₆ alkyl group which may be substituted byone or more fluorine atoms (preferably, a C₁₋₁₆ perfluoroalkyl group),Rf² is a C₁₋₁₆ alkyl group which may be substituted by one or morefluorine atoms (preferably, a C₁₋₁₆ perfluoroalkyl group), a fluorineatom or a hydrogen atom, and more preferably, Rf and Rf² is eachindependently a C₁-3 perfluoroalkyl group.

Subscripts a′, b′, c′ and d′ are the repeating number of each of fourrepeating units of perfluoropolyether which constitute a main backboneof the polymer, and are each independently an integer of 0 or more and300 or less, and the sum of a′, b′, c′ and d′ is at least 1, preferably1-300, more preferably 20-300. The occurrence order of the respectiverepeating units in parentheses with the subscript a′, b′, c′ or d′ isnot limited in the formulae. Among these repeating units, the —(OC₄F₈)—group may be any of —(OCF₂CF₂CF₂CF₂)—, —(OCF(CF₃) CF₂CF₂)—,—(OCF₂CF(CF₃) CF₂)—, —(OCF₂CF₂CF(CF₃))—, —(OC(CF₃)₂CF₂)—,—(OCF₂C(CF₃)₂)—, —(OCF(CF₃) CF(CF₃))—, —(OCF(C₂F₅) CF₂)— and—(OCF₂CF(C₂F₅))—, preferably —(OCF₂CF₂CF₂CF₂). The —(OC₃F₆)— group maybe any of —(OCF₂CF₂CF₂)—, —(OCF(CF₃) CF₂)— and —(OCF₂CF(CF₃))—,preferably —(OCF₂CF₂CF₂)—. The —(OC₂F₄)— group may be any of —(OCF₂CF₂)—and —(OCF(CF₃))—, preferably —(OCF₂CF₂)—.

Examples of the perfluoropolyether compound of the above general formula(3) include a compound of any of the following general formulae (3a) and(3b) (may be one compound or a mixture of two or more compounds).

Rf¹—(OCF₂CF₂CF₂)_(b″)—Rf²  (3a)

Rf¹—(OCF₂CF₂CF₂)_(a″)—(OCF₂CF₂CF₂)_(b″)—(OCF₂CF₂)_(c″)—(OCF₂)_(d″)—Rf²  (3b)

In these formulae:

Rf¹ and Rf² are as defined above; in the formula (3a), b″ is an integerof 1 or more and 100 or less; and in the formula (3b), a″ and b″ areeach independently an integer of 0 or more and 30 or less, for example 1or more and 30 or less, and c″ and d″ are each independently an integerof 1 or more and 300 or less. The occurrence order of the respectiverepeating units in parentheses with the subscript a″, b″, c″ or d″ isnot limited in the formulae.

The above-mentioned fluorine-containing oil may have an averagemolecular weight of 1,000-30,000. By having such average molecularweight, high surface slip property can be obtained.

The fluorine-containing oil may be contained in the surface-treatingagent of the present invention, for example, at 0-500 parts by mass,preferably 0-400 parts by mass, more preferably 5-300 parts by mass withrespect to 100 parts by mass of the perfluoro(poly)ether groupcontaining silane compound (as the total mass when two or more compoundsare used; hereinafter the same shall apply).

The compound of the general formula (3a) and the compound of the generalformula (3b) may be used alone or in combination. The compound of thegeneral formula (3b) is preferable than the compound of the generalformula (3a) since the compound of the general formula (3b) provideshigher surface slip property than the compound of the general formula(3a). When they are used in combination, the ratio by mass of thecompound of the general formula (3a) to the compound of the generalformula (3b) is preferably 1:1 to 1:30, more preferably 1:1 to 1:10. Byapplying such ratio by mass, a perfluoropolyether group-containingsilane-based coating which provides a good balance of surface slipproperty and friction durability can be obtained.

In one embodiment, the fluorine-containing oil comprises one or morecompounds of the general formula (3b) In such embodiment, the mass ratioof the perfluoro(poly)ether group containing silane compound to thecompound of the formula (3b) in the surface-treating agent is preferably10:1 to 1:10, more preferably 4:1 to 1:4.

In one embodiment, a number average molecular weight of the compound ofthe formula (3a) is preferably 2,000-8,000.

In one embodiment, a number average molecular weight of the compound ofthe formula (3b) is preferably 8,000-30,000.

In another embodiment, a number average molecular weight of the compoundof the formula (3b) is preferably 3,000-8,000.

In a preferable embodiment, when a surface-treating layer is formed byusing vacuum deposition, a number average molecular weight of thefluorine-containing oil may be higher than a number average molecularweight of the perfluoro(poly)ether group containing silane compound. Byselecting such number average molecular weights, more excellent surfaceslip property and friction durability can be obtained.

From the other point of view, the fluorine-containing oil may be acompound of the general formula Rf³—F wherein Rf³ is a C₅₋₁₆perfluoroalkyl group. In addition, the fluorine-containing oil may be achlorotrifluoroethylene oligomer. The compound of Rf³—F or thechlorotrifluoroethylene oligomer is preferable because the compoundshave high affinity for the fluorine-containing compound having acarbon-carbon unsaturated bond at the molecular terminal wherein aterminal is a C₁₋₁₆ perfluoroalkyl group.

The fluorine-containing oil contributes to increasing of surface slipproperty of the surface-treating layer.

Examples of the above-mentioned silicone oil include, for example, aliner or cyclic silicone oil having 2,000 or less siloxane bonds. Theliner silicone oil may be so-called a straight silicone oil and amodified silicon oil. Examples of the straight silicone oil includedimethylsilicone oil, methylphenylsilicone oil, andmethylhydrogensilicone oil. Examples of the modified silicone oilinclude that which is obtained by modifying a straight silicone oil withalkyl, aralkyl, polyether, higher fatty acid ester, fluoroalkyl, amino,epoxy, carboxyl, alcohol, or the like. Examples of the cyclic siliconeoil include, for example, cyclic dimethylsiloxane oil.

The silicone oil may be contained in the surface-treating agent of thepresent invention, for example, at 0-300 parts by mass, preferably 0-200parts by mass with respect to 100 parts by mass of thefluorine-containing compound having a carbon-carbon unsaturated bond atthe molecular terminal (as the total mass when two or more compounds areused; hereinafter the same shall apply).

The silicone oil contributes to increasing of surface slip property ofthe surface-treating layer.

Examples of the above-mentioned catalyst include an acid (for example,acetic acid, trifluoroacetic acid, etc.), a base (for example, ammonia,triethylamine, diethylamine, etc.), a transition metal (for example, Ti,Ni, Sn, etc.), and the like.

The catalyst facilitates hydrolysis and dehydration-condensation of theperfluoro(poly)ether group containing silane compound to facilitate aformation of the surface-treating layer.

The surface-treating agent of the present invention is impregnated intoa porous material, for example, a porous ceramic material, a metal fiberfor example that obtained by solidifying a steel wool to obtain apellet. The pellet can be used, for example, in vacuum deposition.

Next, the article of the present invention will be described.

The article of the present invention comprises a base material and alayer (surface-treating layer) which is formed from the surface-treatingagent of the present invention on the surface of the base material. Thisarticle can be produced, for example, as follows.

Firstly, the base material is provided. The base material usable in thepresent invention may be composed of any suitable material such as aglass, a sapphire glass, a resin (may be a natural or synthetic resinsuch as a common plastic material, and may be in form of a plate, afilm, or others), a metal (may be a simple substance of a metal such asaluminum, copper, or iron, or a complex such as alloy or the like), aceramic, a semiconductor (silicon, germanium, or the like), a fiber (afabric, a non-woven fabric, or the like), a fur, a leather, a wood, apottery, a stone, an architectural member or the like. The base materialis preferably a glass or a sapphire glass.

As the glass, a soda-lime glass, an alkali aluminosilicate glass, aborosilicate glass, a non-alkaline glass, a crystal glass, a quartzglass is preferable, a chemically strengthened soda-lime glass, achemically strengthened alkali aluminosilicate glass, and a chemicallystrengthened borosilicate glass are more preferable.

As the resin, an acrylic resin or a polycarbonate resin are preferable.

For example, when an article to be produced is an optical member, amaterial constituting the surface of the base material may be a materialfor an optical member, for example, a glass or a transparent plastic.For example, when an article to be produced is an optical member, anylayer (or film) such as a hard coating layer or an antireflection layermay be formed on the surface (outermost layer) of the base material. Asthe antireflection layer, either a single antireflection layer or amulti antireflection layer may be used. Examples of an inorganicmaterial usable in the antireflection layer include SiO₂, SiO, ZrO₂,TiO₂, TiO, Ti₂O₃, Ti₂O₅, Al₂O₃, Ta₂O₅, CeO₂, MgO, Y₂O₃, SnO₂, MgF₂, WO₃,and the like. These inorganic materials may be used alone or incombination with two or more (for example, as a mixture). When multiantireflection layer is formed, preferably, SiO₂ and/or SiO are used inthe outermost layer. When an article to be produced is an optical glasspart for a touch panel, it may have a transparent electrode, forexample, a thin layer comprising indium tin oxide (ITO), indium zincoxide, or the like on a part of the surface of the base material(glass). Furthermore, the base material may have an insulating layer, anadhesive layer, a protecting layer, a decorated frame layer (I-CON), anatomizing layer, a hard coating layer, a polarizing film, a phasedifference film, a liquid crystal display module, and the like,depending on its specific specification.

The shape of the base material is not specifically limited. The regionof the surface of the base material on which the surface-treating layershould be formed may be at least a part of the surface of the basematerial, and may be appropriately determined depending on use, thespecific specification, and the like of the article to be produced.

The base material may be that of which at least the surface consists ofa material originally having a hydroxyl group. Examples of such materialinclude a glass, in addition, a metal on which a natural oxidized filmor a thermal oxidized film is formed (in particular, a base metal), aceramic, a semiconductor, and the like. Alternatively, as in a resin,when the hydroxyl groups are present but not sufficient, or when thehydroxyl group is originally absent, the hydroxyl group can beintroduced on the surface of the base material, or the number of thehydroxyl group can be increased by subjecting the base material to anypretreatment. Examples of the pretreatment include a plasma treatment(for example, corona discharge) or an ion beam irradiation. The plasmatreatment may be suitably used to introduce the hydroxyl group into orincrease it on the surface of the base material, further, to clarify thesurface of the base material (remove foreign materials, and the like).Alternatively, other examples of the pretreatment include a methodwherein a monolayer of a surface adsorbent having a carbon-carbonunsaturated bond group is formed on the surface of the base material byusing a LB method (Langmuir-Blodgett method) or a chemical adsorptionmethod beforehand, and then, cleaving the unsaturated bond under anatmosphere of oxygen and nitrogen.

Alternatively, the base material may be that of which at least thesurface consists of a material comprising other reactive group such as asilicon compound having one or more Si—H groups or alkoxysilane.

Next, the film of the above surface-treating agent of the presentinvention is formed on the surface of the base material, and the film ispost-treated, as necessary, and thereby the surface-treating layer isformed from the surface-treating agent.

The formation of the film of the surface-treating agent of the presentinvention can be performed by applying the above surface-treating agenton the surface of the base material such that the surface-treating agentcoats the surface. The method of coating is not specifically limited.For example, a wet coating method or a dry coating method can be used.

Examples of the wet coating method include dip coating, spin coating,flow coating, spray coating, roll coating, gravure coating, and asimilar method.

Examples of the dry coating method include deposition (usually, vacuumdeposition), sputtering, CVD and a similar method. The specific examplesof the deposition method (usually, vacuum deposition) include resistanceheating, electron beam, high-frequency heating using microwave, etc.,ion beam, and a similar method. The specific examples of the CVD methodinclude plasma-CVD, optical CVD, thermal CVD and a similar method. Thedeposition method is will be described below in more detail.

Additionally, coating can be performed by an atmospheric pressure plasmamethod.

When the wet coating method is used, the surface-treating agent of thepresent invention is diluted with a solvent, and then it is applied tothe surface of the base material. In view of stability of thesurface-treating agent of the present invention and volatile property ofthe solvent, the following solvents are preferably used: a C₅₋₁₂aliphatic perfluorohydrocarbon (for example, perfluorohexane,perfluoromethylcyclohexane and perfluoro-1,3-dimethylcyclohexane); anaromatic polyfluorohydrocarbon (for example,bis(trifluoromethyl)benzene); an aliphatic polyfluorohydrocarbon (forexample, C₆F₁₃CH₂CH₃ (for example, ASAHIKLIN (registered trademark)AC-6000 manufactured by Asahi Glass Co., Ltd.),1,1,2,2,3,3,4-heptafluorocyclopentane (for example, ZEORORA (registeredtrademark) H manufactured by Nippon Zeon Co., Ltd.); hydrofluorocarbon(HFC) (for example, 1,1,1,3,3-pentafluorobutane (HFC-365mfc));hydrochlorofluorocarbon (for example, HCFC-225 (ASAHIKLIN (registeredtrademark) AK225)); a hydrofluoroether (HFE) (for example, an alkylperfluoroalkyl ether such as perfluoropropyl methyl ether (C₃F₇OCH₃)(for example, Novec (trademark) 7000 manufactured by Sumitomo 3M Ltd.),perfluorobutyl methyl ether (C₄F₉OCH₃) (for example, Novec (trademark)7100 manufactured by Sumitomo 3M Ltd.), perfluorobutyl ethyl ether(C₄F₉OC₂H₅) (for example, Novec (trademark) 7200 manufactured bySumitomo 3M Ltd.), and perfluorohexyl methyl ether (C₂F₅CF(OCH₃)C₃F₇)(for example, Novec (trademark) 7300 manufactured by Sumitomo 3M Ltd.)(the perfluoroalkyl group and the alkyl group may be liner orbranched)), or CF₃CH₂OCF₂CHF₂ (for example, ASAHIKLIN (registeredtrademark) AE-3000 manufactured by Asahi Glass Co., Ltd.),1,2-dichloro-1,3,3,3-tetrafluoro-1-propene (for example, VERTREL(registered trademark) Sion manufactured by Du Pont-MitsuiFluorochemicals Co., Ltd.) and the like. These solvents may be usedalone or as a mixture of 2 or more compound. Among them, thehydrofluoroether is preferable, perfluorobutyl methyl ether (C₄F₉OCH₃)and/or perfluorobutyl ethyl ether (C₄F₉OC₂H₅) are particularlypreferable. Furthermore, the solvent can be mixed with another solvent,for example, to adjust solubility of the perfluoro(poly)ether groupcontaining silane compound.

When the dry coating method is used, the surface-treating agent of thepresent invention may be directly subjected to the dry coating method,or may be diluted with a solvent, and then subjected to the dry coatingmethod.

The formation of the film is preferably performed so that thesurface-treating agent of the present invention is present together witha catalyst for hydrolysis and dehydration-condensation in the coating.Simply, when the wet coating method is used, after the surface-treatingagent of the present invention is diluted with a solvent, and just priorto applying it to the surface of the base material, the catalyst may beadded to the diluted solution of the surface-treating agent of thepresent invention. When the dry coating method is used, thesurface-treating agent of the present invention to which a catalyst hasbeen added is used itself in deposition (usually, vacuum deposition), orpellets may be used in the deposition (usually, the vacuum deposition),wherein the pellets is obtained by impregnating a porous metal such asiron or copper with the surface-treating agent of the present inventionto which the catalyst has been added.

As the catalyst, any suitable acid or base can be used. As the acidcatalyst, for example, acetic acid, formic acid, trifluoroacetic acid,or the like can be used. As the base catalyst, for example, ammonia, anorganic amine, or the like can be used.

Next, the film is post-treated as necessary. This post-treatment is, butnot limited to, a treatment in which water supplying and dry heating aresequentially performed, in more particular, may be performed as follows.

After the film of the surface-treating agent of the present invention isformed on the surface of the base material as mentioned above, water issupplied to this film (hereinafter, referred to as precursor coating).The method of supplying water may be, for example, a method using dewcondensation due to the temperature difference between the precursorcoating (and the base material) and ambient atmosphere or spraying ofwater vapor (steam), but not specifically limited thereto.

It is considered that, when water is supplied to the precursor coating,water acts on a hydrolyzable group bonding to Si present in theperfluoro(poly)ether group containing silane compound in thesurface-treating agent of the present invention, thereby enabling rapidhydrolysis of the compound.

The supplying of water may be performed under an atmosphere, forexample, at a temperature of 0-250° C., preferably 60° C. or more, morepreferably 100° C. or more and preferably 180° C. or less, morepreferably 150° C. By supplying water at such temperature range,hydrolysis can proceed. The pressure at this time is not specificallylimited but simply may be ambient pressure.

Then, the precursor coating is heated on the surface of the basematerial under a dry atmosphere over 60° C. The method of dry heatingmay be to place the precursor coating together with the base material inan atmosphere at a temperature over 60° C., preferably over 100° C., andfor example, of 250° C. or less, preferably of 180° C. or less, and atunsaturated water vapor pressure, but not specifically limited thereto.The pressure at this time is not specifically limited but simply may beambient pressure.

Under such atmosphere, between the PFPE containing silane compound ofthe present inventions, the groups bonding to Si after hydrolysis arerapidly dehydration-condensed with each other. Furthermore, between thecompound and the base material, the group bonding to Si in the compoundafter hydrolysis and a reactive group present on the surface of the basematerial are rapidly reacted, and when the reactive group present on thesurface of the base material is a hydroxyl group,dehydration-condensation is caused. As the result, the bond between theperfluoro(poly)ether group containing silane compound and the basematerial is formed.

The above supplying of water and dry heating may be sequentiallyperformed by using a superheated water vapor.

The superheated water vapor is a gas which is obtained by heating asaturated water vapor to a temperature over the boiling point, whereinthe gas, under an ambient pressure, has become to have a unsaturatedwater vapor pressure by heating to a temperature over 100° C., generallyof 500° C. or less, for example, of 300° C. or less, and over theboiling point. In the present invention, in view of suppressingdecomposition of the perfluoro(poly)ether group containing silanecompound, the superheated water vapor of preferably 250° C. or less,preferably 180° C. or less is used in the supplying of water and dryheating. When the base material on which the precursor coating is formedis exposed to a superheated water vapor, firstly, due to the temperaturedifference between the superheated water vapor and the precursor coatingof a relatively low temperature, dew condensation is generated on thesurface of the precursor coating, thereby supplying water to theprecursor coating. Presently, as the temperature difference between thesuperheated water vapor and the precursor coating decreases, water onthe surface of the precursor coating is evaporated under the dryatmosphere of the superheated water vapor, and an amount of water on thesurface of the precursor coating gradually decreases. During the amountof water on the surface of the precursor coating is decreasing, that is,during the precursor coating is under the dry atmosphere, the precursorcoating on the surface of the base material contacts with thesuperheated water vapor, as a result, the precursor coating is heated tothe temperature of the superheated water vapor (temperature over 100° C.under ambient pressure). Therefore, by using a superheated water vapor,supplying of water and dry heating are enabled to be sequentiallycarried out simply by exposing the base material on which the precursorcoating is formed to a superheated water vapor.

As mentioned above, the post-treatment can be performed. It is notedthat though the post-treatment may be performed in order to furtherincrease friction durability, it is not essential in the producing ofthe article of the present invention. For example, after applying thesurface-treating agent to the surface of the base material, it may beenough to only stand the base material.

As described above, the surface-treating layer derived from the film ofthe surface-treating agent of the present invention is formed on thesurface of the base material to produce the article of the presentinvention. The surface-treating layer thus formed has high frictiondurability. Furthermore, this surface-treating layer may havewater-repellency, oil-repellency, antifouling property (for example,preventing from adhering a fouling such as fingerprints), waterproofproperty (preventing the ingress of water into an electrical member, andthe like), surface slip property (or lubricity, for example, wipingproperty of a fouling such as fingerprints and excellent tactile feelingin a finger) depending on a composition of the surface-treating agentused, in addition to high friction durability, thus may be suitably usedas a functional thin film.

The article having the surface-treating layer obtained according to thepresent invention is not specifically limited to, but may be an opticalmember. Examples of the optical member include the followings: displayssuch as a cathode ray tube (CRT; for example, TV, personal computermonitor), a liquid crystal display, a plasma display, an organic ELdisplay, an inorganic thin-film EL dot matrix display, a rear projectiondisplay, a vacuum fluorescent display (VFD), a field emission display(FED; Field Emission Display), or a front surface protective plate, anantireflection plate, a polarizing plate, or an anti-glare plate ofthese display, or these whose surface is subjected to antireflectiontreatment; lens of glasses, or the like; a touch panel sheet of aninstrument such as a mobile phone or a personal digital assistance; adisk surface of an optical disk such as a Blu-ray disk, a DVD disk, aCD-R or MO; an optical fiber, and the like; a display surface of aclock.

Other article having the surface-treating layer obtained according tothe present invention may be also a ceramic product, a painted surface,a cloth product, a leather product, a medical product and a plaster.

The article having the surface-treating layer obtained according to thepresent invention may be also a medical equipment or a medical material

The thickness of the surface-treating layer is not specifically limited.For the optical member, the thickness of the surface-treating layer iswithin the range of 1-50 nm, preferably 1-30 nm, more preferably 1-15nm, in view of optical performance, surface slip property, frictiondurability and antifouling property.

Hereinbefore, the article produced by using the surface-treating agentof the present invention is described in detail. It is noted that anapplication, a method for using or a method for producing the articleare not limited to the above exemplification.

EXAMPLES

The surface-treating agent of the present invention will be described indetail through Examples, although the present invention is not limitedto Examples. It is noted that in Examples, all chemical formulaedescribed below mean an average composition.

The perfluoro(poly)ether group containing silane compounds listed inTable 1 were used. The proportion of the compound having a molecularweight of 3,000 or less was determined based on a GPC (Gel PermeationChromatography) measurement. The measurement condition is describedbelow.

(GPC Measurement)

The measurement was conducted by using the system in which the columnsbelow [manufactured by SHOWA DENKO K.K.] were connected in series inthis order. It is noted that the molecular weight was calibrated byusing perfluoropolyether oil A, B, C.

Samples for Calibration

Perfluoropolyether oil A: Number average molecular weight 7250 Mw/Mn1.08

Perfluoropolyether oil B: Number average molecular weight 4180 Mw/Mn1.08

Perfluoropolyether oil C: Number average molecular weight 2725 Mw/Mn1.08

Column

GPC KF-G (4.6 mmI.D.×1 cm)

GPC KF806L (8.0 mmI.D.×30 cm)

GPC KF806L (8.0 mmI.D.×30 cm)

Apparatus

GPCmax (HPLC system) and, TDA-302 (detector) manufactured by MalvernInstruments

Eluate

ASAHIKLIN AK225 (HCFC-225)/1,1,1,3,3,3-hexafluoro-2-propanol [90/10(w/w)]

Concentration of Sample

20 mg/mL

TABLE 1 Proportion of compound Mn** Mw** having a Number Weightmolecular average average weight of Chemical m** molecular molecular3,000 or formula* (average) weight weight less (mol %) Compound 1Chemical 35 5690 6030 0.5 formula A Compound 2 Chemical 32 5600 6710 1.9formula B Compound 3 Chemical 48 8240 10300 0.1 formula A Compound 4Chemical 22 3920 4160 9.6 formula A Compound 5 Chemical 21 3980 445013.8 formula B Compound 6 Chemical 12 2570 2640 81.7 formula A *Chemicalformula A and B are as follows. Chemical formula A

Chemical formula BCF₃CF₂CF₂O(CF₂CF₂CF₂O)_(m)CF₂CF₂CH₂OCH₂CH₂CH₂Si[CH₂CH₂CH₂Si(OCH₃)₃]₃**The value of m means a value measured by ¹⁹F-NMR, Mn and Mw mean avalue measured by GPC.

The compound listed in the following table was dissolved inhydrofluoroether (Novec HFE7200 manufactured by Sumitomo 3M Ltd.)) suchthat the concentration was 20 wt % to prepare Surface-treating agent.Surface-treating agent prepared in the above was vacuum deposited on achemical strengthening glass (Gorilla glass manufactured by CorningIncorporated; thickness: 0.7 mm). Processing condition of the vacuumdeposition was a pressure of 3.0×10⁻³ Pa. Firstly, silicon dioxide wasdeposited on the surface of this chemical strengthening glass in amanner of an electron-beam deposition. Subsequently, thesurface-treating agent of 2 mg (that is, it contained of 0.4 mg of theperfluoro(poly)ether group containing silane compound) wasvacuum-deposited per one plate of the chemical strengthening glass (55mm×100 mm). Then, the chemical strengthening glass having the depositedlayer was stood under a temperature of 20° C. and a humidity of 65% for24 hours.

TABLE 2 Compound used Amount of deposition Example 1 Compound 1 0.4 mgExample 2 Compound 2 0.4 mg Example 3 1:1 Mixture of Compound 3 0.2 mgper each and Compound 4 total 0.4 mg (Proportion of the compound havinga molecular weight of 3000 or less is 4.5 mol %) Mn: 5620, Mw: 6860Example 4 1:1 Mixture of Compound 1 compound 1: 0.37 and Compound 6 mg(Proportion of the compound Compound 6: 0.03 having a molecular weightmg of 3000 or less is 6.7 Total 0.4 mg mol %) Mn: 5580, Mw: 5900Comparative Compound 4 0.4 mg example 1 Comparative Compound 5 0.4 mgexample 2 Comparative Compound 6 0.4 mg example 3 Comparative 5:1mixture of Compound 1 Compound 1: 0.33 example 4 and Compound 6 mg(Proportion of the compound Compound 6: 0.07 having a molecular weightmg of 3000 or less is 12.8 Total 0.4 mg mol %) Mn: 5380, Mw: 5790

Evaluation

Evaluation of Friction Durability

A static water contact angle of the surface-treating layers formed onthe surface of the base material in the above Examples 1-4 andComparative Examples 1-4 respectively was measured. The static watercontact angle was measured for 1 μL of water by using a contact anglemeasuring instrument (manufactured by KYOWA INTERFACE SCIENCE Co.,Ltd.).

Firstly, as an initial evaluation, the static water contact angle of thesurface-treating layer of which the surface had not still contacted withanything after formation thereof was measured (the number of rubbing iszero).

As an evaluation of the friction durability, a steel wool frictiondurability evaluation was performed. Specifically, the base material onwhich the surface-treating layer was formed was horizontally arranged,and then, a steel wool (grade No. #0000; dimension: 5 mm×10 mm×10 mm)was contacted with the exposed surface of the surface-treating layer anda load of 1000 gf was applied thereon. Then, the steel wool was shuttledat a rate of 140 mm/second while applying the load. The static watercontact angle (degree) was measured per a predetermined shuttlingnumber. The evaluation was stopped when the measured value of thecontact angle became to be less than 100 degree. It is noted that forExample 2, the evaluation was stopped at 20,000 shuttles because ofabrasion of the steel wool. The results are shown in the followingTable.

TABLE 3 Proportion of the compound steel wool having a molecular weightdurability (times) of 3000 or less (mol %) Example 1 15,000 0.5 Example2 20,000 or more 1.9 Example 3 15,000 4.5 Example 4 12,500 6.7Comparative 5,000 9.6 Example 1 Comparative 12,500 13.8 Example 2Comparative 2,000 81.7 Example 3 Comparative 7,500 12.8 Example 4

As understood from Table 3, it was confirmed that the surface-treatingagents that the proportion of the compound having a molecular weight of3000 or less was within the scope of the present invention (Examples1-4) could provide excellent friction durability. On the other hand, thesurface-treating agents (Comparative Examples 1-4) that the proportionof the compound having a molecular weight of 3000 or less was is higherthan 9.0 mol % had less friction durability in comparison with thesurface-treating agent of the present invention. Although the presentinvention is not bound to any theory, a reason for this is presumed asfollows: when the proportion of the compound having a molecular weightof 3000 or less is too high, this compound having low molecular weightfirstly binds to the base material, and inhibits the binding of thecompound having high molecular weight and high function to the basematerial.

INDUSTRIAL APPLICABILITY

The present invention is suitably applied for forming a surface-treatinglayer on a surface of various base materials, in particular, an opticalmember in which transparency is required.

1. A surface-treating agent comprising at least one perfluoro(poly)ethergroup containing silane compound of any of the formulae (A1), (A2),(B1), (B2), (C1) and (C2):

wherein: PFPE is each independently at each occurrence a group of theformula:—(OC₄F₈)_(a)—(OC₃F₆)_(b)—(OC₂F₄)_(c)—(OCF₂)_(d)— wherein a, b, c and dare each independently an integer of 0-200, the sum of a, b, c and d is1 or more, and the occurrence order of the respective repeating units inparentheses with the subscript a, b, c or d is not limited in theformula; Rf is each independently at each occurrence an alkyl grouphaving 1-16 carbon atoms which may be substituted by one or morefluorine atoms; R¹ is each independently at each occurrence a hydrogenatom or an alkyl group having 1-22 carbon atoms; R² is eachindependently at each occurrence a hydroxyl group or a hydrolyzablegroup; R¹¹ is each independently at each occurrence a hydrogen atom or ahalogen atom; R¹² is each independently at each occurrence a hydrogenatom or a lower alkyl group; n is, independently per a unit (—SiR¹_(n)R² _(3-n)), an integer of 0-3; there is at least one R² in theformulae (A1), (A2), (B1) and (B2); X¹ is each independently a singlebond or a 2-10 valent organic group; X² is each independently at eachoccurrence a single bond or a divalent organic group; t is eachindependently at each occurrence an integer of 1-10; α is eachindependently an integer of 1-9; α′ is each independently an integer of1-9; X⁵ is each independently a single bond or a 2-10 valent organicgroup; β is each independently an integer of 1-9; β′ is eachindependently an integer of 1-9; X⁷ is each independently a single bondor a 2-10 valent organic group; γ is each independently an integer of1-9; γ′ is each independently an integer of 1-9; R^(a) is eachindependently at each occurrence —Z—SiR⁷¹ _(p)R⁷² _(q)R⁷³ _(r); Z iseach independently at each occurrence an oxygen atom or a divalentorganic group; R⁷¹ is each independently at each occurrence R^(a′);R^(a′) has the same definition as that of R^(a); in R^(a), the number ofSi atoms which are straightly linked via the Z group is up to five; R⁷²is each independently at each occurrence a hydroxyl group or ahydrolyzable group; R⁷³ is each independently at each occurrence ahydrogen atom or a lower alkyl group; p is each independently at eachoccurrence an integer of 0-3; q is each independently at each occurrencean integer of 0-3; r is each independently at each occurrence an integerof 0-3; in one R^(a), the sum of p, q and r is 3, and there is at leastone R⁷² in the formula (C1) and (C2); R^(b) is each independently ateach occurrence a hydroxyl group or a hydrolyzable group; R^(c) is eachindependently at each occurrence a hydrogen atom or a lower alkyl group;k is each independently at each occurrence an integer of 1-3; l is eachindependently at each occurrence an integer of 0-2; m is eachindependently at each occurrence an integer of 0-2; and the sum of k, land m is 3 in each unit in parentheses with the subscript γ, wherein aproportion of the perfluoro(poly)ether group containing silane compoundhaving a molecular weight of 3,000 or less in the perfluoro(poly)ethergroup containing silane compounds of any of the above general formulaeis 9 mol % or less.
 2. The surface-treating agent according to claim 1wherein the proportion of the perfluoro(poly)ether group containingsilane compound having a molecular weight of 3,000 or less in theperfluoro(poly)ether group containing silane compounds of any of theabove general formulae is 7 mol % or less.
 3. The surface-treating agentaccording to claim 1 wherein the proportion of the perfluoro(poly)ethergroup containing silane compound having a molecular weight of 3,000 orless in the perfluoro(poly)ether group containing silane compounds ofany of the above general formulae is 5 mol % or less.
 4. Thesurface-treating agent according to claim 1 wherein Rf is aperfluoroalkyl group having 1-16 carbon atoms.
 5. The surface-treatingagent according to claim 1 wherein PFPE is a group of any of thefollowing formulas (i) to (iv):—(OCF₂CF₂CF₂)_(b)—  (i) wherein b is an integer of 1-200;—(OCF(CF₃)CF₂)_(b)—  (ii) wherein b is an integer of 1-200;—(OCF₂CF₂CF₂CF₂)_(a)—(OCF₂CF₂CF₂)_(b)—(OCF₂CF₂)_(c)—(OCF₂)_(d)—  (iii)wherein a and b are each independently 0 or an integer of 1-30, c and dare each independently an integer of 1-200, and the occurrence order ofthe respective repeating units in parentheses with the subscript a, b, cor d is not limited in the formula; or—(OC₂F₄—R⁸)_(f)—  (iv) wherein R⁸ is a group selected from OC₂F₄, OC₃F₆and OC₄F₈; and f is an integer of 2-100.
 6. The surface-treating agentaccording to claim 1 wherein X¹, X⁵ and X⁷ are each independently a 2-4valent organic group, α, β and γ are each independently 1-3, and α′, β′and γ′ are
 1. 7. The surface-treating agent according to claim 1 whereinX¹, X⁵ and X⁷ are a divalent organic group, α, β and γ are 1, and α′, β′and γ′ are
 1. 8. The surface-treating agent according to claim 7 whereinX¹, X⁵ and X⁷ are each independently —(R³¹)_(p)—(X^(a))_(q′)— wherein:R³¹ is a single bond, —(CH₂)_(s′)— (wherein s′ is an integer of 1-20) ora o-, m- or p-phenylene group; X^(a) is —(X^(b))_(l′)— (wherein l′ is aninteger of 1-10); X^(b) is each independently at each occurrenceselected from the group consisting of —O—, —S—, an o-, m- or p-phenylenegroup, —C(O)O—, —Si(R³³)₂—, —(Si(R³³)₂O)_(m′)—Si(R³³)₂— (wherein m′ isan integer of 1-100), —CONR³⁴—, —O—CONR³⁴—, —NR³⁴— and —(CH₂)_(n′)—(wherein n′ is an integer of 1-20); R³³ is each independently at eachoccurrence a phenyl group, a C₁₋₆ alkyl group or a C₁₋₆ alkoxy group;R³⁴ is each independently at each occurrence a hydrogen atom, a phenylgroup or a C₁₋₆ alkyl group; p′ is 0 or 1; q′ is 0 or 1; at least one ofp′ and q′ is 1, the occurrence order of the respective repeating unitsin parentheses with the subscript p′ or q′ is not limited in theformula; and R³¹ and X^(a) is may be substituted with one or moresubstituents selected from a fluorine atom, a C₁₋₃ alkyl group and aC₁₋₃ fluoroalkyl group.
 9. The surface-treating agent according to claim7 wherein X¹, X⁵ and X⁷ are each independently selected from the groupconsisting of: —CH₂O(CH₂)₂—, —CH₂O(CH₂)₃—, —CH₂O(CH₂)₆—,—CH₂O(CH₂)₃Si(CH₃)₂OSi(CH₃)₂(CH₂)₂—,—CH₂O(CH₂)₃Si(CH₃)₂OSi(CH₃)₂OSi(CH₃)₂(CH₂)₂—,—CH₂O(CH₂)₃Si(CH₃)₂O(Si(CH₃)₂O)₂Si(CH₃)₂(CH₂)₂—,—CH₂O(CH₂)₃Si(CH₃)₂O(Si(CH₃)₂O)₃Si(CH₃)₂(CH₂)₂—,—CH₂O(CH₂)₃Si(CH₃)₂O(Si(CH₃)₂O)₁₀Si(CH₃)₂(CH₂)₂—,—CH₂O(CH₂)₃Si(CH₃)₂O(Si(CH₃)₂O)₂₀Si(CH₃)₂(CH₂)₂—, —CH₂OCF₂CHFOCF₂—,—CH₂OCF₂CHFOCF₂CF₂—, —CH₂OCF₂CHFOCF₂CF₂CF₂—, —CH₂OCH₂CF₂CF₂OCF₂—,—CH₂OCH₂CF₂CF₂OCF₂CF₂—, —CH₂OCH₂CF₂CF₂OCF₂CF₂CF₂—,—CH₂OCH₂CF₂CF₂OCF(CF₂)CF₂OCF₂—, —CH₂OCH₂CF₂CF₂OCF(CF₃)CF₂OCF₂CF₂—,—CH₂OCH₂CF₂CF₂OCF(CF₂)CF₂OCF₂CF₂CF₂—, —CH₂OCH₂CHFCF₂OCF₂—,—CH₂OCH₂CHFCF₂OCF₂CF₂—, —CH₂OCH₂CHFCF₂OCF₂CF₂CF₂—,—CH₂OCH₂CHFCF₂OCF(CF₂)CF₂OCF₂—, —CH₂OCH₂CHFCF₂OCF(CF₂)CF₂OCF₂CF₂—,—CH₂OCH₂CHFCF₂OCF(CF₃)CF₂OCF₂CF₂CF₂—,—CH₂OCH₂(CH₂)₇CH₂Si(OCH₃)₂OSi(OCH₃)₂(CH₂)₂Si(OCH₃)₂OSi(OCH₃)₂(CH₂)₃—,—CH₂OCH₂CH₂CH₂Si(OCH₃)₂OSi(OCH₂)₂(CH₂)₂—,—CH₂OCH₂CH₂CH₂Si(OCH₂CH₂)₂OSi(OCH₂CH₃)₂(CH₂)₂—,—CH₂OCH₂CH₂CH₂Si(OCH₃)₂OSi(OCH₃)₂(CH₂)₂—,—CH₂OCH₂CH₂CH₂Si(OCH₂CH₃)₂OSi(OCH₂CH₃)₂(CH₂), —(CH₂)₂—, —(CH₂)₃—,—(CH₂)₄—, —(CH₂)₆—, —(CH₂)₂—Si(CH₃)₂—(CH₂)₂—, —CONH—(CH₂)₃—,—CON(CH₃)—(CH₂)₃—, —CON(Ph)-(CH₂)₃— (wherein Ph is a phenyl group),—CONH—(CH₂)₆—, —CON(CH₃)—(CH₂)₆—, —CON(Ph)-(CH₂)₆— (wherein Ph is aphenyl group), —CONH—(CH₂)₂NH(CH₂)₃—, —CONH—(CH₂)₆NH(CH₂)₃—,—CH₂O—CONH—(CH₂)₃—, —CH₂O—CONH—(CH₂)₆—, —S—(CH₂)₃—, —(CH₂)₂S(CH₂)₃—,—CONH—(CH₂)₃Si(CH₃)₂OSi(CH₃)₂(CH₂)₂—,—CONH—(CH₂)₃Si(CH₃)₂OSi(CH₃)₂OSi(CH₃)₂(CH₃)₂—,—CONH—(CH₂)₃Si(CH₃)₂O(Si(CH₃)₂O)₂Si(CH₃)₂(CH₃)₂—,—CONH—(CH₂)₃Si(CH₃)₂O(Si(CH₃)₂O)₃Si(CH₃)₂(CH₃)₂—,—CONH—(CH₂)₃Si(CH₃)₂O(Si(CH₃)₂O)₁₀Si(CH₃)₂(CH₃)₂—,—CONH—(CH₂)₃Si(CH₃)₂O(Si(CH₃)₂O)₂)₂₀Si(CH₃)₂(CH₂)₂—, —C(O)O—(CH₂)₃—,—C(O)O—(CH₂)₆—, —CH₂—O—(CH₂)₃—Si(CH₃)₂—(CH₂)₂—Si(CH₃)₂—(CH₂)₂—,—CH₂—O—(CH₂)₃—Si(CH₃)₂—(CH₂)₂—Si(CH₃)₂—CH(CH₃)—,—CH₂—O—(CH₂)₃—Si(CH₃)₂—(CH₂)₂—Si(CH₃)₂—(CH₂)₃—,—CH₂—O—(CH₂)₃—Si(CH₃)₂—(CH₂)₂—Si(CH₃)₂—CH(CH₃)—CH₂—,


10. The surface-treating agent according to claim 1 wherein X¹ is—O—CFR¹³—(CF₂)_(e)—, R¹³ is a fluorine atom or a lower fluoroalkylgroup, and e is 0 or
 1. 11. The surface-treating agent according toclaim 1 wherein X² is —(CH₂)_(s)—, and s is an integer of 0-2.
 12. Thesurface-treating agent according to claim 1 wherein k is 3, and q is 3in R^(a).
 13. The surface-treating agent according to claim 1 whereinX¹, X⁵ and X⁷ are each independently a 3-10 valent organic group. 14.The surface-treating agent according to claim 13 wherein X¹, X⁵ and X⁷are each independently selected from the group consisting of:

wherein in each group, at least one of T is the following group attachedto PFPE in the formulae (A1), (A2), (B1), (B2), (C1) and (C2):—CH₂O(CH₂)₂—, —CH₂O(CH₂)₃—, —CF₂O(CH₂)₃—, —(CH₂)₂—, —(CH₂)₃—, —(CH₂)₄—,—CONH—(CH₂)₃—, —CON(CH₃)—(CH₂)₃—, —CON(Ph)-(CH₂)₃— (wherein Ph is aphenyl group), and

at least one of the other T is —(CH₂)_(n)— (wherein n is an integer of2-6) attached to the carbon atom or the Si atom in the formulae (A1),(A2), (B1), (B2), (C1) and (C2) and the others are each independently amethyl group, a phenyl group, a alkoxy having 1-6 carbon atoms, or aradical scavenger group or an ultraviolet ray absorbing group, R⁴¹ iseach independently a hydrogen atom, a phenyl group, an alkoxy grouphaving 1 to 6 carbon atoms or an alkyl group having 1 to 6 carbon atoms,and R⁴² is each independently a hydrogen atom, a C₁₋₆ alkyl group or aC₁₋₆ alkoxy group.
 15. The surface-treating agent according to claim 1wherein the perfluoro(poly)ether group containing silane compound is atleast one compound of any of the formulae (A1) and (A2).
 16. Thesurface-treating agent according to claim 1 wherein theperfluoro(poly)ether group containing silane compound is at least onecompound of any of the formulae (B1) and (B2).
 17. The surface-treatingagent a claim 1 wherein the perfluoro(poly)ether group containing silanecompound is at least one compound of any of the formulae (C1) and (C2).18. The surface-treating agent according to claim 1 further comprisingone or more components selected form a fluorine-containing oil, asilicone oil and a catalyst.
 19. The surface-treating agent according toclaim 18 wherein the fluorine-containing oil is one or more compounds ofthe formula (3):R²¹—(OC₄F₈)_(a′)—(OC₃F₆)_(b′)—(OC₂F₄)_(c′)—(OCF₂)_(d′)—R²²  (3) wherein:R²¹ is an alkyl group having 1-16 carbon atoms which may be substitutedby one or more fluorine atoms; R²² is an alkyl group having 1-16 carbonatoms which may be substituted by one or more fluorine atoms, a fluorineatom or a hydrogen atom; and a′, b′, c′ and d′ are the repeating numberof each of four repeating units of perfluoro(poly)ether which constitutea main backbone of the polymer, and are each independently an integer of0 or more and 300 or less, the sum of a′, b′, c′ and d′ is 1 or more,and the occurrence order of the respective repeating units inparentheses with the subscript a′, b′, c′ and d′ is not limited in theformula.
 20. The surface-treating agent according to claim 18 whereinthe fluorine-containing oil is one or more compounds of the formula (3a)or (3b):R²¹—(OCF₂CF₂CF₂)_(b″)—R²²  (3a)R²¹—(OCF₂CF₂CF₂CF₂)_(a″)—(OCF₂CF₂CF₂)_(b″)—(OCF₂CF₂)_(c″)—(OCF₂)_(d″)—R²²  (3b)wherein: R²¹ is an alkyl group having 1-16 carbon atoms which may besubstituted by one or more fluorine atoms; R²² is an alkyl group having1-16 carbon atoms which may be substituted by one or more fluorineatoms, a fluorine atom or a hydrogen atom; in the formula (3a), b″ is aninteger of 1 or more and 100 or less; in the formula (3b), a″ and b″ areeach independently an integer of 0 or more and 30 or less, and c″ and d″are each independently an integer of 1 or more and 300 or less; and theoccurrence order of the respective repeating units in parentheses withthe subscript a″, b″, c″ or d″ is not limited in the formula.
 21. Thesurface-treating agent according to claim 20 wherein a mass ratio of theperfluoro(poly)ether group containing silane compound and the compoundof the formula (3b) is 10:1-1:10.
 22. The surface-treating agentaccording to claim 20 wherein a mass ratio of the perfluoro(poly)ethergroup containing silane compound and the compound of the formula (3b) is4:1-1:4.
 23. The surface-treating agent according to claim 1 wherein thecompound of the formula (3a) has a number average molecular weight of2,000-8,000.
 24. The surface-treating agent according to claim 1 whereinthe compound of the formula (3b) has a number average molecular weightof 8,000-30,000.
 25. The surface-treating agent according to claim 1wherein the compound of the formula (3b) has a number average molecularweight of 3,000-8,000.
 26. The surface-treating agent according to claim1 further comprising a solvent.
 27. The surface-treating agent accordingto claim 1 which is used as an antifouling-coating agent or awater-proof coating agent.
 28. The surface-treating agent according toclaim 1 for vacuum deposition.
 29. A pellet comprising thesurface-treating agent according to claim
 1. 30. An article comprising abase material and a layer which is formed on a surface of the basematerial from the surface-treating agent according to claim
 1. 31. Thearticle according to claim 30 wherein the base material is a glass or asapphire glass.
 32. The article according to claim 31 wherein the glassis a glass selected from the group consisting of a soda-lime glass, analkali aluminosilicate glass, a borosilicate glass, a non-alkalineglass, a crystal glass, and a quartz glass.
 33. The article according toclaim 30 wherein the article is an optical member.
 34. The articleaccording to claim 30 wherein the article is a display.